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1.
Bouchard, Frédéric.
Quantum Cryptography Beyond Qubits
.
Degree: 2019, University of Ottawa
URL: http://hdl.handle.net/10393/39731
► Over the last few decades, quantum cryptography has been one of the most important quantum technologies developed. It holds the promise of communicating secure information…
(more)
▼ Over the last few decades, quantum cryptography has been one of the most important quantum technologies developed. It holds the promise of communicating secure information over untrusted channels. In particular, quantum cryptography is immune to the eventual threats posed by large-scale quantum computers, which is not the case for our current classical cryptography infrastructures. In a world where information, communication and privacy are of paramount importance, the development of secure quantum communication infrastructures becomes imperative. So far, most of the quantum cryptographic systems developed to date are based on two-dimensional encoding schemes, analogous to classical bits, known as qubits. Nevertheless, other than for the polarization of light, photonic degrees of freedom, i.e. position, momentum, time and frequency, naturally occur as high-dimensional quantum systems. Moreover, by considering high-dimensional encoding schemes beyond qubits, advantages in terms of information capacity and noise tolerance are predicted in theory. In this thesis, the basic components of a high-dimensional quantum cryptographic system are investigated. We begin by reviewing important developments in quantum cryptography and high-dimensional quantum information. As a starting point, two different quantum information tasks, i.e. optimal quantum cloning and quantum metrology, are experimentally investigated for high-dimensional quantum systems in order to demonstrate the numerous advantages of performing quantum tasks beyond qubits. The photonic degree of freedom used in these experiments, known as transverse spatial modes, is obtained by combining the position and momentum photonics degrees of freedom. Thus, we develop a novel method to measure high-dimensional quantum states encoded in arbitrary spatial modes. Using a similar characterization technique, several high-dimensional quantum communication channels are characterized to perform high-dimensional quantum cryptography. The tools developed in the laboratory are then brought to realistic conditions in order to test the feasibility of high-dimensional quantum cryptography. Two different types of quantum channels are experimentally investigated, namely an intra-city 300 m long free-space link and a short 3 m outdoor underwater link. Finally, we investigate and compare novel high-dimensional protocols to overcome current limitations.
Subjects/Keywords: Quantum
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APA ·
Chicago ·
MLA ·
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Export
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APA (6th Edition):
Bouchard, F. (2019). Quantum Cryptography Beyond Qubits
. (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/39731
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bouchard, Frédéric. “Quantum Cryptography Beyond Qubits
.” 2019. Thesis, University of Ottawa. Accessed April 18, 2021.
http://hdl.handle.net/10393/39731.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bouchard, Frédéric. “Quantum Cryptography Beyond Qubits
.” 2019. Web. 18 Apr 2021.
Vancouver:
Bouchard F. Quantum Cryptography Beyond Qubits
. [Internet] [Thesis]. University of Ottawa; 2019. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10393/39731.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bouchard F. Quantum Cryptography Beyond Qubits
. [Thesis]. University of Ottawa; 2019. Available from: http://hdl.handle.net/10393/39731
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Urbana-Champaign
2.
Banerjee, Tuseeta.
Path integral methods for quantum dynamics in condensed phases.
Degree: PhD, Chemistry, 2015, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/89036
► Quantum mechanical effects play an important role in dynamics of condensed phases. It is also well known that the difficulty of solving the full Schrödinger…
(more)
▼ Quantum mechanical effects play an important role in dynamics of condensed phases. It is also well known that the difficulty of solving the full Schrödinger equation grows exponentially with time. One approach to cope up with this difficulty is to restrict
quantum treatment to a few particles (system) and treat the dynamics of the rest of particles (bath) using classical trajectories. Path integral methods due to their trajectory like nature provide excellent tool to develop
quantum-classical methods, but to capture long time dynamics, the number of classical trajectories grow exponentially. A part of this work focuses on improving
Quantum-Classical Path Integral (QCPI) treatments that allow for larger path integral time step by building “smarter” propagators. These improved solvent-driven reference propagators is developed by incorporating physically motivated approximations to the solvent. When used in QCPI expression they allow convergence with larger time steps leading to an exponential reduction of the number of trajectories required. Further advantages of these propagators include improvements in path filtering techniques, smaller number of path integral steps for achieving the memory decoherence time, and smoothing of the integrand which leads to convergence with fewer Monte Carlo sample points. These ideas have been validated on the spin boson model - a prototypical model to study condensed phase dynamics, which consists of a two-level system coupled to a harmonic bath. The new approach of building the reference propagators combined with their iterative evaluation and filtering is validated using parameters that mimic the first electron transfer in wild-type photosynthetic reaction centres. A real-world dynamical simulation contains various anharmonic effects, Ferrocene (donor) - Ferrocenium (acceptor) system in liquid Benzene was studied where the anharmonic effects of the bath of liquid Benzene on the dynamics of the system were treated using Ensemble Averaged Classical Path. The process of electron or proton transfer occurs between two species having different charges and fluctuations in the solvent plays a key role in determining the rates of such reaction dynamics. To correctly account for the effects of initial distribution of the solvent on the dynamics of the
quantum system, the
concept of equilibrating the bath to the donor state of the system is used. Two different approaches have been used within the influence functional framework.
Advisors/Committee Members: Makri, Nancy (advisor), Makri, Nancy (Committee Chair), Hirata, So (committee member), Luthey-Schulten, Zan (committee member), Schweizer, Kenneth (committee member).
Subjects/Keywords: quantum
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Banerjee, T. (2015). Path integral methods for quantum dynamics in condensed phases. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/89036
Chicago Manual of Style (16th Edition):
Banerjee, Tuseeta. “Path integral methods for quantum dynamics in condensed phases.” 2015. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed April 18, 2021.
http://hdl.handle.net/2142/89036.
MLA Handbook (7th Edition):
Banerjee, Tuseeta. “Path integral methods for quantum dynamics in condensed phases.” 2015. Web. 18 Apr 2021.
Vancouver:
Banerjee T. Path integral methods for quantum dynamics in condensed phases. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2015. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/2142/89036.
Council of Science Editors:
Banerjee T. Path integral methods for quantum dynamics in condensed phases. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/89036

Texas A&M University
3.
Fan, Longfei.
Quantum Measurement and Its Applications in Quantum Optical Systems.
Degree: PhD, Physics, 2018, Texas A&M University
URL: http://hdl.handle.net/1969.1/174040
► Quantum measurement is the cornerstone of quantum computing and quantum information. It has many exciting applications. Various quantum optical systems are key to experimental physics…
(more)
▼ Quantum measurement is the cornerstone of
quantum computing and
quantum information. It
has many exciting applications. Various
quantum optical systems are key to experimental physics
because of their high precision and well controllability. In this dissertation, we focus on study of
quantum measurement and its applications in
quantum optical systems. We first study the fundamental
trade-off relation between information gain and fidelity during successive weak QND
measurement. Then we evaluate the effectiveness of
quantum measurement reversal on
quantum
state protection under non-ideal detection efficiency. A linear optical setup is proposed for experimental
verification of our result. Finally, we explore the performance of non-Gaussian two-mode
entangled states for
quantum illumination, which is an application of
quantum state discrimination.
For successive weak QND measurements, we show that the information gain increases monotonically
with respect to the number of measurements. Meanwhile the fidelity shows oscillatory
decreasing behavior, which results from interference terms between photon numbers. We conclude
that a greater information gain does not always imply a worse fidelity. For non-ideal
quantum measurement
reversal, we derive how
quantum states evolve in
quantum reversal under finite effective
monitoring efficiency. Fidelity and concurrence are then calculated to evaluate the effectiveness
of state protection using reversal. Generally the performance is weakened by finite monitoring
efficiency. The negative effect of measurement reversal can dominate under certain conditions. A
criterion that decides whether to apply state protection using measurement reversal is given. As
for
quantum illumination, we conclude that non-Gaussian operations can enhance the performance,
i.e., achieve lower error probability by introducing both stronger entanglement and larger average
photon numbers. However, if the signal strength is a concern, two-mode squeezed states (TMSS)
performs better than other non-Gaussian states under the same output signal strength. When applying
a coherent superposition of photon subtraction and photon addition to enhance
quantum
illumination, we show that optimal error probability is achieved by an asymmetrical operation.
Advisors/Committee Members: Zubairy, Muhammad Suhail (advisor), Zheltikov, Aleksei (committee member), Sokolov, Alexei (committee member), Hemmer, Philip (committee member).
Subjects/Keywords: quantum information; quantum measurement; quantum optics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fan, L. (2018). Quantum Measurement and Its Applications in Quantum Optical Systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174040
Chicago Manual of Style (16th Edition):
Fan, Longfei. “Quantum Measurement and Its Applications in Quantum Optical Systems.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 18, 2021.
http://hdl.handle.net/1969.1/174040.
MLA Handbook (7th Edition):
Fan, Longfei. “Quantum Measurement and Its Applications in Quantum Optical Systems.” 2018. Web. 18 Apr 2021.
Vancouver:
Fan L. Quantum Measurement and Its Applications in Quantum Optical Systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1969.1/174040.
Council of Science Editors:
Fan L. Quantum Measurement and Its Applications in Quantum Optical Systems. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174040

University of Waterloo
4.
Marwah, Ashutosh Satyajit.
Optical Quantum Communication & Cryptography with Temporarily Trusted Parties.
Degree: 2019, University of Waterloo
URL: http://hdl.handle.net/10012/15087
► The work in this thesis can be divided into three parts. The first two parts deal with optical quantum communication protocols and the third part…
(more)
▼ The work in this thesis can be divided into three parts. The first two parts deal with optical quantum communication protocols and the third part deals with quantum cryptography. The first part of the thesis is a step towards reformulating quantum protocols in terms of coherent states. Quantum communication protocols are typically formulated in terms of abstract qudit states and operations. This leaves the question of an experimental realization open. Direct translation of these protocols, say into single photons with some d-dimensional degree of freedom, are typically challenging to realize. Multi-mode coherent states, on the other hand, can be easily generated experimentally. Reformulation of protocols in terms of these states has been a successful strategy for implementation of quantum protocols. Quantum key distribution and the quantum fingerprinting protocol have both followed this route. In Chapter 3, we characterize the Gram matrices of multi-mode coherent states in an attempt to understand the class of communication protocols, which can be implemented using these states. We also derive the closure of the Gram matrices, which can be implemented in this way, so that we also characterize those matrices, which can be approximated arbitrarily well using multi-mode coherent states.
In the second part of the thesis, Chapter 4, we describe our collaboration with an experimental group to implement the quantum fingerprinting protocol and examine the tradeoffs between the resources required to implement such protocols. It is seen that it is difficult to implement the quantum fingerprinting protocol experimentally for large input sizes. This leads us to study the tradeoff between the two resources expended during optically implemented simultaneous message passing communication protocols: the duration of the protocol and the energy required to run it. We derive general bounds on the growth of these quantities which are valid for all optical protocols. We also develop tighter bounds for the growth of these resources for protocols implementing quantum fingerprinting with coherent states.
Finally in Chapter 5, we venture into quantum cryptography. We introduce a new setting for two-party cryptography with temporarily trusted third parties. In this setting, in addition to Alice and Bob, there are third parties, which Alice and Bob both trust to be honest during the course of the protocol. However, once the protocol concludes, there is no guarantee over the behaviour of these third parties. It is possible that they collaborate and act adversarially against the honest parties. We implement a variant of bit commitment in this setting, which we call erasable bit commitment. In this primitive, Alice has the choice of either opening or erasing her commitment after the commit phase. The ability to ask for an erasure allows Alice to ask the trusted nodes to erase her commitment in case the trust period is about to expire. However, this ability also makes erasable bit commitment weaker than the standard version of bit…
Subjects/Keywords: quantum communication; quantum optics; quantum cryptography
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Marwah, A. S. (2019). Optical Quantum Communication & Cryptography with Temporarily Trusted Parties. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15087
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Marwah, Ashutosh Satyajit. “Optical Quantum Communication & Cryptography with Temporarily Trusted Parties.” 2019. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/15087.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Marwah, Ashutosh Satyajit. “Optical Quantum Communication & Cryptography with Temporarily Trusted Parties.” 2019. Web. 18 Apr 2021.
Vancouver:
Marwah AS. Optical Quantum Communication & Cryptography with Temporarily Trusted Parties. [Internet] [Thesis]. University of Waterloo; 2019. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/15087.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Marwah AS. Optical Quantum Communication & Cryptography with Temporarily Trusted Parties. [Thesis]. University of Waterloo; 2019. Available from: http://hdl.handle.net/10012/15087
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
5.
Daley, Patrick.
Causal Discovery of Photonic Bell Experiments.
Degree: 2020, University of Waterloo
URL: http://hdl.handle.net/10012/15446
► A causal understanding of a physical theory is vital. They provide profound insights into the implications of the theory and contain the information required to…
(more)
▼ A causal understanding of a physical theory is vital. They provide profound insights into the implications of the theory and contain the information required to manipulate, not only predict, our surroundings. Unfortunately, one of the most broadly used and successful theories, quantum theory, continues to evade a satisfactory causal description. The progress is hindered by the difficulty of faithfully testing causal explanations in an experimental setting. This thesis presents a novel causal discovery algorithm which allows a direct comparison of a wide variety of causal explanations for experimental data. They include causal influences both classical and quantum mechanical in nature. First we provide relevant background information, predominately on quantum mechanics, quantum optics and statistical inference. Next, we review the framework of classical causality and the connection between a causal assumption and statistical model. We then present a novel causal discovery algorithm for noisy experimental data. Finally, we perform two Bell experiments and apply the newly developed algorithm on the resulting data.
The causal discovery algorithm operates on observational data without any interven- tions required. It utilizes the concept of predictive accuracy to assign a score to each causal explanation. This allows the simultaneous consideration of classical and quantum causal theories. In addition, this approach allows the identification of overly complex explanations as these perform poorly with respect to this criterion.
Both experiments are implemented using quantum optics. The first Bell experiment has a near maximally entangled shared resource state while the second has a separable resource state. The results indicate that a quantum local causal explanation bests describes the first experiment, whereas a classical local causal explanation is preferred for the second. A super-luminal or super-deterministic theory are sub-optimal for both.
Subjects/Keywords: quantum foundations; causal inference; quantum optics; quantum
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Daley, P. (2020). Causal Discovery of Photonic Bell Experiments. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15446
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Daley, Patrick. “Causal Discovery of Photonic Bell Experiments.” 2020. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/15446.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Daley, Patrick. “Causal Discovery of Photonic Bell Experiments.” 2020. Web. 18 Apr 2021.
Vancouver:
Daley P. Causal Discovery of Photonic Bell Experiments. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/15446.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Daley P. Causal Discovery of Photonic Bell Experiments. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/15446
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
6.
Kothari, Robin.
Efficient algorithms in quantum query complexity.
Degree: 2014, University of Waterloo
URL: http://hdl.handle.net/10012/8625
► In this thesis we provide new upper and lower bounds on the quantum query complexity of a diverse set of problems. Specifically, we study quantum…
(more)
▼ In this thesis we provide new upper and lower bounds on the quantum query complexity of a diverse set of problems. Specifically, we study quantum algorithms for Hamiltonian simulation, matrix multiplication, oracle identification, and graph-property recognition.
For the Hamiltonian simulation problem, we provide a quantum algorithm with query complexity sublogarithmic in the inverse error, an exponential improvement over previous methods. Our algorithm is based on a new quantum algorithm for implementing unitary matrices that can be written as linear combinations of efficiently implementable unitary gates. This algorithm uses a new form of ``oblivious amplitude amplification'' that can be applied even though the reflection about the input state is unavailable.
In the oracle identification problem, we are given oracle access to an unknown N-bit string x promised to belong to a known set of size M, and our task is to identify x. We present the first quantum algorithm for the problem that is optimal in its dependence on N and M. Our algorithm is based on ideas from classical learning theory and a new composition theorem for solutions of the filtered gamma2-norm semidefinite program.
We then study the quantum query complexity of matrix multiplication and related problems over rings, semirings, and the Boolean semiring in particular. Our main result is an output-sensitive algorithm for Boolean matrix multiplication that multiplies two n x n Boolean matrices with query complexity O(n sqrt{l}), where l is the sparsity of the output matrix. The algorithm is based on a reduction to the graph collision problem and a new algorithm for graph collision.
Finally, we study the quantum query complexity of minor-closed graph properties and show that most minor-closed properties – those that cannot be characterized by a finite set of forbidden subgraphs – have quantum query complexity Theta(n3/2) and those that do have such a characterization can be solved strictly faster, with o(n3/2) queries. Our lower bound is based on a detailed analysis of the structure of minor-closed properties with respect to forbidden topological minors and forbidden subgraphs. Our algorithms are a novel application of the quantum walk search framework and give improved upper bounds for several subgraph-finding problems.
Subjects/Keywords: Quantum computing; Quantum algorithms; Quantum query complexity
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kothari, R. (2014). Efficient algorithms in quantum query complexity. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/8625
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kothari, Robin. “Efficient algorithms in quantum query complexity.” 2014. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/8625.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kothari, Robin. “Efficient algorithms in quantum query complexity.” 2014. Web. 18 Apr 2021.
Vancouver:
Kothari R. Efficient algorithms in quantum query complexity. [Internet] [Thesis]. University of Waterloo; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/8625.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kothari R. Efficient algorithms in quantum query complexity. [Thesis]. University of Waterloo; 2014. Available from: http://hdl.handle.net/10012/8625
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley
7.
Freeman, Christian Daniel.
The Toric Code at Finite Temperature.
Degree: Physics, 2018, University of California – Berkeley
URL: http://www.escholarship.org/uc/item/56k7v7kq
► Alexei Kitaev's toric code is a rich model, that has birthed and stimulated the development of topological quantum computing, error correction, and field theory. It…
(more)
▼ Alexei Kitaev's toric code is a rich model, that has birthed and stimulated the development of topological quantum computing, error correction, and field theory. It was also the first example of a quantum error correcting code that could resiliently store quantum information in certain types of noisy environments without the need for active error correction. Unfortunately, the toric code loses much of its power as a noise-resilient quantum memory at any finite temperature. Many of the problems with the toric code at finite temperature are likewise shared among its cousin stabilizer codes. These problems can be traced to the proliferation of stringlike ``defects'' in these codes at finite temperature. The aim of this thesis is then twofold.First, I characterize both numerically and theoretically the failure modes of the toric code at finite temperature with fairly modest bath assumptions. I achieve this by numerically sampling the nonequilibrium dynamics of the toric code using a continuous time monte carlo algorithm. From this analysis, I was able to derive an exact expression for the low and high temperature dynamics of the toric code, as well as a regime over which the toric code is ``most'' stable to noise.Secondly, by leveraging the results of this analysis, I construct algorithms that aim to suppress these noise channels. These algorithms are broadly separated into measurement-free and few-measurement protocols. The measurement-free algorithms are reminiscent of dynamical-decoupling pulse sequences, applied in parallel or in serial to a target stabilizer code, and are entirely unitary. I find that measurement-free algorithms can provide a constant factor increase to the lifetime of a large class of stabilizer codes at finite temperature. The few-measurement protocols are more complex, but I provide evidence that they can provide a threshold for the toric code with asymptotically fewer measurements than was previously known to be achievable.
Subjects/Keywords: Quantum physics; quantum error correction; quantum memory
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Freeman, C. D. (2018). The Toric Code at Finite Temperature. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/56k7v7kq
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Freeman, Christian Daniel. “The Toric Code at Finite Temperature.” 2018. Thesis, University of California – Berkeley. Accessed April 18, 2021.
http://www.escholarship.org/uc/item/56k7v7kq.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Freeman, Christian Daniel. “The Toric Code at Finite Temperature.” 2018. Web. 18 Apr 2021.
Vancouver:
Freeman CD. The Toric Code at Finite Temperature. [Internet] [Thesis]. University of California – Berkeley; 2018. [cited 2021 Apr 18].
Available from: http://www.escholarship.org/uc/item/56k7v7kq.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Freeman CD. The Toric Code at Finite Temperature. [Thesis]. University of California – Berkeley; 2018. Available from: http://www.escholarship.org/uc/item/56k7v7kq
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Nelson Mandela Metropolitan University
8.
Tile, Ngcali.
AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots.
Degree: 2018, Nelson Mandela Metropolitan University
URL: http://hdl.handle.net/10948/36716
► GaSb/GaAs quantum dots (QD) were grown by atmospheric pressure (AP) metal-organic vapour phase epitaxy (MOVPE) using triethylgallium (TEGa), tertiarybutylarsine (tBAs) and trimethylantimony (TMSb) as gallium…
(more)
▼ GaSb/GaAs quantum dots (QD) were grown by atmospheric pressure (AP) metal-organic vapour phase epitaxy (MOVPE) using triethylgallium (TEGa), tertiarybutylarsine (tBAs) and trimethylantimony (TMSb) as gallium (Ga), arsenic (As) and (Sb) sources, respectively. The effect of AP-MOVPE growth parameters on the formation of GaSb QD structures on GaAs was studied. The formation of small, coherent GaSb dots on GaAs improved with decreasing V/III ratios, which were controlled through changing either the TMSb/TEGa ratio at a constant growth temperature or changing the growth temperature at a constant TMSb/TEGa ratio. The maximum effective V/III ratio for dot formation was 0.175. The dot density was more sensitive to growth time than to source mole fraction in the reactor, since time determines the amount of deposited material. The dot density increased with increasing growth time, while the shape and size of the dots were more sensitive to the source vapour mole fraction, which controls the growth rate. Lower mole fractions resulted in smaller sized dots with a more uniform distribution compared to higher mole fractions. Dome-shaped dots with densities as high as 4×1010 cm-2, average base length of 35 nm and average height of 5 nm were achieved. Capping of GaSb QDs at high temperatures caused flattening and the formation of a thin, inhomogeneous GaSb layer inside GaAs. No obvious QD photoluminescence (PL) peak was detected for these samples. A two stage process for capping the dots (involving growth of a low temperature GaAs cap, followed by a high temperature cap) led to the retention of the dot-like features in/on a wetting layer (WL) of GaSb and distinct PL peaks for both the QDs and WL. An increase in excitation power during PL measurements for this particular sample caused the QD and WL peaks to shift to higher energies. This is attributed to electrostatic band bending, leading to triangular potential wells, typical for type II band alignment between GaAs and strained GaSb. Variable temperature PL measurements showed the decrease in the intensity of the WL peak to be faster than that of the QD peak as the measurement temperature increased. A detailed high resolution transmission electron microscopy analysis was performed to study the morphology and chemical interaction between GaAs and GaSb regions for capped GaSb/GaAs QDs. The capped dots had dimensions similar to those of uncapped dots and had a higher concentration of Sb at their center, with the periphery being intermixed with GaAs. Measurement of lattice strain performed inside these dots revealed the strain to be distributed inhomogenously throughout the dot area. The effect of GaAs host matrix on excitonic behaviour in AP-MOVPE grown GaSb/GaAs quantum dots was investigated. Room temperature (RT) PL emission was achieved from a single layer of quantum dots by controlling the GaAs host matrix growth temperature. These samples were prepared using a GaSb dot growth temperature of 530 °C, followed by growth of a thin GaAs ‘cold’ cap, before depositing the final part of…
Subjects/Keywords: Quantum theory; Quantum electronics; Quantum dots; Semiconductors
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tile, N. (2018). AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots. (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/36716
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tile, Ngcali. “AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots.” 2018. Thesis, Nelson Mandela Metropolitan University. Accessed April 18, 2021.
http://hdl.handle.net/10948/36716.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tile, Ngcali. “AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots.” 2018. Web. 18 Apr 2021.
Vancouver:
Tile N. AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots. [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2018. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10948/36716.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tile N. AP-MOVPE growth and characterisation of GaSb/GaAs quantum dots. [Thesis]. Nelson Mandela Metropolitan University; 2018. Available from: http://hdl.handle.net/10948/36716
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
9.
Schmitz, Albert Thomas.
Quantum Walks: Theory, Application, And Implementation.
Degree: MS, Physics & Astrophysics, 2016, University of North Dakota
URL: https://commons.und.edu/theses/1959
► The quantum walk is a method for conceptualizing and designing quantum computing algorithms and it comes in two forms: the continuous-time and discrete-time quantum…
(more)
▼ The
quantum walk is a method for conceptualizing and designing
quantum computing algorithms and it comes in two forms: the continuous-time and discrete-time
quantum walk. The thesis is organized into three parts, each of which looks to develop the concept and uses of the
quantum walk. The first part is the theory of the
quantum walk. This includes definitions and considerations for the various incarnations of the discrete-time
quantum walk and a discussion on the general method for connecting the continuous-time and discrete-time versions. As a result, it is shown that most versions of the discrete-time
quantum walk can be put into a general form and this can be used to simulate any continuous-time
quantum walk. The second part uses these results for a hypothetical application. The application presented is a search algorithm that appears to scale in the time for completion independent of the size of the search space. This behavior is then elaborated upon and shown to have general qualitative agreement with simulations to within the approximations that are made. The third part introduces a method of implementation. Given a universal
quantum computer, the method is discussed and shown to simulate an arbitrary discrete-time
quantum walk. Some of the benefits of this method are that half the unitary evolution can be achieved without the use of any gates and there may be some possibility for error detection. The three parts combined suggest a possible experiment, given a
quantum computing scheme of sufficient robustness.
Advisors/Committee Members: William W. Schwalm.
Subjects/Keywords: Quantum Algorithm; Quantum Computing; Quantum Walks
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APA ·
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MLA ·
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APA (6th Edition):
Schmitz, A. T. (2016). Quantum Walks: Theory, Application, And Implementation. (Masters Thesis). University of North Dakota. Retrieved from https://commons.und.edu/theses/1959
Chicago Manual of Style (16th Edition):
Schmitz, Albert Thomas. “Quantum Walks: Theory, Application, And Implementation.” 2016. Masters Thesis, University of North Dakota. Accessed April 18, 2021.
https://commons.und.edu/theses/1959.
MLA Handbook (7th Edition):
Schmitz, Albert Thomas. “Quantum Walks: Theory, Application, And Implementation.” 2016. Web. 18 Apr 2021.
Vancouver:
Schmitz AT. Quantum Walks: Theory, Application, And Implementation. [Internet] [Masters thesis]. University of North Dakota; 2016. [cited 2021 Apr 18].
Available from: https://commons.und.edu/theses/1959.
Council of Science Editors:
Schmitz AT. Quantum Walks: Theory, Application, And Implementation. [Masters Thesis]. University of North Dakota; 2016. Available from: https://commons.und.edu/theses/1959

University of Technology, Sydney
10.
Su, Zhaofeng.
Quantification and distribution of genuinely nonlocal resources.
Degree: 2018, University of Technology, Sydney
URL: http://hdl.handle.net/10453/129356
► Quantum mechanics is nonlocal, which makes it different from classical mechanics. Quantum information and quantum computation is a promising frontier science which is based on…
(more)
▼ Quantum mechanics is nonlocal, which makes it different from classical mechanics. Quantum information and quantum computation is a promising frontier science which is based on quantum mechanics. The nonlocality of quantum mechanics is the fundamental reason that many quantum information processing tasks have significant advantages over their classical counterparts.
In this dissertation, we study three aspects of quantum nonlocality, which include the quantitative relationship between entanglement and nonlocality, the quantification of genuine tripartite nonlocality and the distribution of nonlocal quantum resources. To be specific,
• We investigate the quantitative relationship between entanglement and nonlocality of bipartite quantum systems. We start by exploiting the condition that the nonlocality of two different two-qubit states can be optimally examined by a same nonlocality test setting. Via numerical simulation, we find that the nonlocality of a generic two-qubit state is upper bounded by a function of the corresponding entanglement. Further, we give an analytical proof for the upper bound and find the class of two-qubit states that can reach the upper bound.
• We analyze the quantification of genuine tripartite nonlocality of a generic three-qubit state. We find a method to solve the problem for a special class of three-qubit states which include not only pure states but also mixed states. Applying the method, we drive analytical results for the genuine tripartite nonlocality of generalized GHZ states, generalized Werner states and two class of mixed states with special correlation matrices.
• We investigate the distribution of nonlocal quantum resources. To distribute bipartite nonlocal quantum resources, we design an efficient quantum repeater scheme, which not only achieves the optimal transmission rate but also consumes less resources of local operations and classical communication, for the case of general pure states of two-qubit system. We also analyze the case of bipartite pure states of arbitrary dimensional quantum system and get an upper bound on the probability of a successful projection operation to produce a maximally nonlocal state. To distribute tripartite nonlocal resources, we propose a simple scenario to generate tripartite nonlocal resources from bipartite nonlocal resources. As examples, we examine the cases that two-qubit Werner states and general two-qubit pure states are prepared as resources, respectively. We get the upper bounds on the genuine tripartite nonlocality that can be generated in the scenario. We also provide the optimal measurement settings to achieve the upper bounds.
Subjects/Keywords: Quantum mechanics; Quantum nonlocality; Bipartite quantum systems
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Su, Z. (2018). Quantification and distribution of genuinely nonlocal resources. (Thesis). University of Technology, Sydney. Retrieved from http://hdl.handle.net/10453/129356
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Su, Zhaofeng. “Quantification and distribution of genuinely nonlocal resources.” 2018. Thesis, University of Technology, Sydney. Accessed April 18, 2021.
http://hdl.handle.net/10453/129356.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Su, Zhaofeng. “Quantification and distribution of genuinely nonlocal resources.” 2018. Web. 18 Apr 2021.
Vancouver:
Su Z. Quantification and distribution of genuinely nonlocal resources. [Internet] [Thesis]. University of Technology, Sydney; 2018. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10453/129356.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Su Z. Quantification and distribution of genuinely nonlocal resources. [Thesis]. University of Technology, Sydney; 2018. Available from: http://hdl.handle.net/10453/129356
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New Mexico
11.
Cesare, Christopher.
Topological Code Architectures for Quantum Computation.
Degree: Physics & Astronomy, 2014, University of New Mexico
URL: http://hdl.handle.net/1928/24543
► This dissertation is concerned with quantum computation using many-body quantum systems encoded in topological codes. The interest in these topological systems has increased in recent…
(more)
▼ This dissertation is concerned with
quantum computation using many-body
quantum systems encoded in topological codes. The interest in these topological systems has increased in recent years as devices in the lab begin to reach the fidelities required for performing arbitrarily long
quantum algorithms. The most well-studied system, Kitaev's toric code, provides both a physical substrate for performing universal fault-tolerant
quantum computations and a useful pedagogical tool for explaining the way other topological codes work. In this dissertation, I first review the necessary formalism for
quantum information and
quantum stabilizer codes, and then I introduce two families of topological codes: Kitaev's toric code and Bombin's color codes. I then present three chapters of original work. First, I explore the distinctness of encoding schemes in the color codes. Second, I introduce a model of
quantum computation based on the toric code that uses adiabatic interpolations between static Hamiltonians with gaps constant in the system size. Lastly, I describe novel state distillation protocols that are naturally suited for topological architectures and show that they provide resource savings in terms of the number of required ancilla states when compared to more traditional approaches to
quantum gate approximation.
Advisors/Committee Members: Landahl, Andrew, Miyake, Akimasa, Allahverdi, Rouzbeh, Deutsch, Ivan.
Subjects/Keywords: physics; quantum; quantum computing; quantum memory
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cesare, C. (2014). Topological Code Architectures for Quantum Computation. (Doctoral Dissertation). University of New Mexico. Retrieved from http://hdl.handle.net/1928/24543
Chicago Manual of Style (16th Edition):
Cesare, Christopher. “Topological Code Architectures for Quantum Computation.” 2014. Doctoral Dissertation, University of New Mexico. Accessed April 18, 2021.
http://hdl.handle.net/1928/24543.
MLA Handbook (7th Edition):
Cesare, Christopher. “Topological Code Architectures for Quantum Computation.” 2014. Web. 18 Apr 2021.
Vancouver:
Cesare C. Topological Code Architectures for Quantum Computation. [Internet] [Doctoral dissertation]. University of New Mexico; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1928/24543.
Council of Science Editors:
Cesare C. Topological Code Architectures for Quantum Computation. [Doctoral Dissertation]. University of New Mexico; 2014. Available from: http://hdl.handle.net/1928/24543

University of New Mexico
12.
Madhok, Vaibhav.
Quantum correlations, chaos and information.
Degree: Physics & Astronomy, 2012, University of New Mexico
URL: http://hdl.handle.net/1928/21057
► Quantum chaos is the study of quantum systems whose classical description is chaotic. How does chaos manifest itself in the quantum world? In this spirit,…
(more)
▼ Quantum chaos is the study of
quantum systems whose classical description is chaotic. How does chaos manifest itself in the
quantum world? In this spirit, we study the dynamical generation of entanglement as a signature of chaos in a system of periodically kicked coupled-tops, where chaos and entanglement arise from the same physical mechanism. The long-time entanglement as a function of the position of an initially localized wave packet very closely correlates with the classical phase space surface of section – it is nearly uniform in the chaotic sea, and reproduces the detailed structure of the regular islands. The uniform value in the chaotic sea is explained by the random state conjecture. As classically chaotic dynamics take localized distributions in phase space to random distributions, quantized versions take localized coherent states to pseudo-random states in Hilbert space. Such random states are highly entangled, with an average value near that of the maximally entangled state. For a map with global chaos, we derive that value based on new analytic results for the entropy of random states. For a mixed phase space, we use the Percival conjecture to identify a "chaotic subspace" of the Hilbert space. The typical entanglement, averaged over the unitarily invariant Haar measure in this subspace, agrees with the long-time averaged entanglement for initial states in the chaotic sea. In all cases the dynamically generated entanglement is that of a random complex vector, even though the system is time-reversal invariant, and the Floquet operator is a member of the circular orthogonal ensemble. Continuing on our journey to find the footprints of chaos in the
quantum world, we explore
quantum signatures of classical chaos by studying the rate of information gain in
quantum tomography. The measurement record is obtained as a sequence of expectation values of a Hermitian operator evolving under repeated application of the Floquet operator of the
quantum kicked top on a large ensemble of identical systems. We find an increase in the rate of information gain and hence higher fidelities in the process when the Floquet maps employed increase in chaoticity. We make predictions for the information gain using random matrix theory in the fully chaotic regime and show a remarkable agreement between the two. Finally we discuss how this approach can be used in general as a benchmark for information gain in an experimental implementation based on nonlinear dynamics of atomic spins measured weakly by the Faraday rotation of a laser probe. The last part of this thesis is devoted to the study of the nature of
quantum correlations themselves.
Quantum correlations are at the heart of the weirdness of
quantum mechanics and at the same time serve as a resource for the potential benefits
quantum information processing might provide. For example, Einstein described
quantum entanglement as "spooky action at a distance" ~. However, even entanglement does not fully capture the complete
quantum character of a…
Advisors/Committee Members: Deutsch, Ivan, Prasad, Sudhakar, Finley, Daniel, Ghose, Shohini.
Subjects/Keywords: Quantum chaos; Quantum entanglement; Quantum computers.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Madhok, V. (2012). Quantum correlations, chaos and information. (Doctoral Dissertation). University of New Mexico. Retrieved from http://hdl.handle.net/1928/21057
Chicago Manual of Style (16th Edition):
Madhok, Vaibhav. “Quantum correlations, chaos and information.” 2012. Doctoral Dissertation, University of New Mexico. Accessed April 18, 2021.
http://hdl.handle.net/1928/21057.
MLA Handbook (7th Edition):
Madhok, Vaibhav. “Quantum correlations, chaos and information.” 2012. Web. 18 Apr 2021.
Vancouver:
Madhok V. Quantum correlations, chaos and information. [Internet] [Doctoral dissertation]. University of New Mexico; 2012. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1928/21057.
Council of Science Editors:
Madhok V. Quantum correlations, chaos and information. [Doctoral Dissertation]. University of New Mexico; 2012. Available from: http://hdl.handle.net/1928/21057

University of Waterloo
13.
Meyer-Scott, Evan.
Heralding Photonic Qubits for Quantum Communication.
Degree: 2016, University of Waterloo
URL: http://hdl.handle.net/10012/10201
► Quantum communication attempts to harness the unique rules of quantum mechanics to perform communication tasks that are difficult or impossible using classical rules. To realize…
(more)
▼ Quantum communication attempts to harness the unique rules of quantum mechanics to perform communication tasks that are difficult or impossible using classical rules. To realize these benefits, information must be carried on quantum systems. Photons make excellent carriers because they interact very little with the environment, move quickly, and can naturally store quantum information in their polarization. However, it is notoriously difficult to detect a single photon without destroying it. Standard detectors simply absorb the photon, losing the quantum information. This is a critical outstanding problem in quantum communication, as advanced protocols need to know exactly when a photon has arrived at a receiver after transmission through the atmosphere or an optical fibre before performing further quantum-information-processing tasks. Certifying a photon’s presence is of particular interest in tests of Bell’s inequalities, which have only recently been performed without loopholes arising from photon loss, and in device-independent quantum cryptography, which relies on such Bell tests for security.
In this thesis, I first present work on directly reducing losses in a successful loophole-free Bell test. This is an extremely difficult task that cannot be extended for long-distance communication. Therefore I then focus on ways to circumvent loss by detecting photons without destroying them while preserving their quantum information. First I analyze theoretically a way to herald photons using only linear-optical elements (beam splitters and phase shifters) and extra ancilla photons. Similar but older methods have been demonstrated experimentally by other groups, and my improvements will help future advanced quantum communication protocols.
The main experiment in this thesis certifies the presence of a photon in a rather simple way: split the photon into two using a nonlinear optical crystal, then detect one of the pair to herald the other. I show in this first proof-of-principle experiment that photonic qubit precertification indeed preserves qubit states, with up to (92.3 ± 0.6)% fidelity and rates of 1100 events per hour. With reductions in detector dark counts, precertification could outperform direct transmission, even with extremely lossy fibre links.
Finally, I present two sources of photons based on nonlinearities in optical fibres. One of the limitations of the photon splitting scheme for heralding is the low success probability due to the very low likelihood of splitting a photon in two. In these fibre photon sources I investigate increasing the splitting likelihood in four-wave mixing through advanced materials and fibre designs. I use polarization-maintaining fibres to generate entangled photon pairs as a prerequisite to precertification, with (92.2 ± 0.2)% fidelity to a maximally-entangled state. Then I show that one type of highly nonlinear chalcogenide glass, never before used for photon pair generation, could outperform standard nonlinear crystals by two orders of magnitude, with calculated…
Subjects/Keywords: quantum optics; quantum information; quantum communication; photonics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Meyer-Scott, E. (2016). Heralding Photonic Qubits for Quantum Communication. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/10201
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Meyer-Scott, Evan. “Heralding Photonic Qubits for Quantum Communication.” 2016. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/10201.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Meyer-Scott, Evan. “Heralding Photonic Qubits for Quantum Communication.” 2016. Web. 18 Apr 2021.
Vancouver:
Meyer-Scott E. Heralding Photonic Qubits for Quantum Communication. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/10201.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Meyer-Scott E. Heralding Photonic Qubits for Quantum Communication. [Thesis]. University of Waterloo; 2016. Available from: http://hdl.handle.net/10012/10201
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
14.
Layden, David.
Indirect Quantum Control: An Implementation-Independent Scheme.
Degree: 2016, University of Waterloo
URL: http://hdl.handle.net/10012/10645
► The ability to control quantum systems rapidly as compared to their coherence times is a central requirement for most proposed quantum technologies, such as quantum…
(more)
▼ The ability to control quantum systems rapidly as compared to their coherence times is a central requirement for most proposed quantum technologies, such as quantum computing and quantum metrology. Improving the ratio of control timescales to coherence times, however, is made difficult by the fact that both timescales depend on the coupling strength between systems and their environment. One promising method of improving this ratio involves indirect control: steering a quantum system via a quantum actuator, rather than by driving it directly. While this approach has shown promise in a variety of experimental
settings, all implementations to date have relied crucially on special properties of the system at hand, and the control schemes they have used are not generally applicable to arbitrary systems.
Here we propose an implementation-independent indirect control scheme. It relies upon an unexpected emergent feature of a model in which a quantum system is made to interact with a rapid succession of ancillas, one at a time. We introduce this model by discussing the quantum Zeno effect, a special instance of quantum control in which a state is preserved through frequent measurements. We then further develop the model and show how it can be used to construct a universal scheme for indirect quantum control. Finally, we discuss the possibility of using this scheme not only for coherent control, but also for dissipative quantum control, which has a number of important applications.
Subjects/Keywords: Quantum physics; Quantum computing; Quantum control
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Layden, D. (2016). Indirect Quantum Control: An Implementation-Independent Scheme. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/10645
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Layden, David. “Indirect Quantum Control: An Implementation-Independent Scheme.” 2016. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/10645.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Layden, David. “Indirect Quantum Control: An Implementation-Independent Scheme.” 2016. Web. 18 Apr 2021.
Vancouver:
Layden D. Indirect Quantum Control: An Implementation-Independent Scheme. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/10645.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Layden D. Indirect Quantum Control: An Implementation-Independent Scheme. [Thesis]. University of Waterloo; 2016. Available from: http://hdl.handle.net/10012/10645
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Macquarie University
15.
Javaherian, Clara.
Quantum transport and switching in long-range coupled quantum systems.
Degree: 2016, Macquarie University
URL: http://hdl.handle.net/1959.14/1249385
► Thesis by publication.
Bibliography: pages 89-97.
1. Introduction – Efficient quantum transport in qubit networks – 3. Geometrical robustness of qubit networks – 4. Switching…
(more)
▼ Thesis by publication.
Bibliography: pages 89-97.
1. Introduction – Efficient quantum transport in qubit networks – 3. Geometrical robustness of qubit networks – 4. Switching application of qubit networks – 5. Conclusion.
Controlling the dynamics of quantum states is a common demand in quantum technology. We theoretically study quantum transport and switching in long-range coupled quantum networks possessing a single excitation. The qubit networks of our study are affected by Markovian environments while one qubit is irreversibly connected to an additional site. Different goals are studied towards controlling quantum transport such as efficient single excitation transfer, switching quantum transport,and manipulating the quantum states of qubit networks. These goals have been previously investigated using different mechanisms, however in this thesis we approach them by proposing appropriate geometrical arrangements of sites.
Regarding efficient single excitation transfer we follow two approaches: Checking if there exist a spatial dimension preference for qubit arrangements towards optimal quantum transport, and whether the efficient network designs are robust against geometrical variations. For dimension analysis a random walk optimization method is used to compare the transport efficiency of networks expanded in one and two spatial dimensions. We find that for some choices of network parameters the two-dimensional networks are slightly more efficient than the one dimensional equivalent networks. This assures that designing one-dimensional qubit channels are adequate for efficient transport and the two-dimensional networks should only be considered where the two-dimensional spatial expansion is more compatible with the surrounding architecture. To design a network, after deciding about the network dimensionality, one may attempt to optimize the channel geometry which might result in a non-robust optimal configuration against the geometrical errors.
To achieve robust optimal configurations we follow two approaches: We investigate the efficient configurations of sites in both one and two dimensional arrangements and present some patterns of robust geometric arrangements of sites in geometrical parameter space. Another approach to achieve robust efficient transport is defining a quantity as the geometrical robustness (georobustness) of qubit networks. By optimising geo-robustness against the network-environment parameters one can efficiently transfer a single excitation with many arbitrary arrangements of the network sites.
Switching of quantum states is another goal towards controlled quantum dynamics. We study the transport characteristics of highly symmetric three-dimensional networks and analytically prove that a fraction of the initially injected excitation can trap for long durations via the creation of dark states. Using this characteristic we suggest switching devices which are robust against environmental noises.
1 online resource (xxxii, 97 pages) illustrations (some colour)
Advisors/Committee Members: Macquarie University. Department of Physics and Astronomy.
Subjects/Keywords: Quantum systems; Quantum theory; quantum transport; switching
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Javaherian, C. (2016). Quantum transport and switching in long-range coupled quantum systems. (Doctoral Dissertation). Macquarie University. Retrieved from http://hdl.handle.net/1959.14/1249385
Chicago Manual of Style (16th Edition):
Javaherian, Clara. “Quantum transport and switching in long-range coupled quantum systems.” 2016. Doctoral Dissertation, Macquarie University. Accessed April 18, 2021.
http://hdl.handle.net/1959.14/1249385.
MLA Handbook (7th Edition):
Javaherian, Clara. “Quantum transport and switching in long-range coupled quantum systems.” 2016. Web. 18 Apr 2021.
Vancouver:
Javaherian C. Quantum transport and switching in long-range coupled quantum systems. [Internet] [Doctoral dissertation]. Macquarie University; 2016. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1959.14/1249385.
Council of Science Editors:
Javaherian C. Quantum transport and switching in long-range coupled quantum systems. [Doctoral Dissertation]. Macquarie University; 2016. Available from: http://hdl.handle.net/1959.14/1249385

University of New South Wales
16.
Wheatley, Trevor.
To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing.
Degree: Engineering & Information Technology, 2016, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/55888
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:39598/SOURCE02?view=true
► Quantum parameter estimation (QPE) is the ability to precisely estimate a classical parameter in a quantum system. QPE is important to many key quantum disciplines…
(more)
▼ Quantum parameter estimation (QPE) is the ability to precisely estimate a classical parameter in a
quantum system. QPE is important to many key
quantum disciplines such as
quantum control, gravitational wave detection and
quantum key distribution. The discipline of QPE is driven by the pursuit of precision limited only by
quantum mechanics, with benchmarks like the standard
quantum limit (SQL) and the illusive Heisenberg limit. Many techniques promising greater precision have been proposed and demonstrated. Here we expand the QPE body of knowledge by demonstrating QPE techniques for estimating optical phase and mirror position in
quantum optical systems. We demonstrate new and existing techniques, comparing the results with existing limits of precision. Our techniques lower traditional precision levels with further improvement obtained when
quantum enhancement is employed.In this thesis we present results from the first demonstrations of adaptive and dual homodyne detection using time-asymmetric
quantum filtering to estimate a continuously varying optical phase. In this work we approach the SQL using dual homodyne detection and go beyond the SQL by 1.2 +/- 0.08 times with an adaptive homodyne measurement.We additionally present results from the first experimental demonstration of optical phase estimation using time-symmetric
quantum smoothing. Here we go beyond the SQL with both dual homodyne and adaptive homodyne by 2.24 +/- 0.14 times for the latter. This is extended to an experimental demonstration of
quantum enhanced optical phase estimation using
quantum smoothing. We define a new limit, the coherent state limit (CSL), our best precision achievable with a coherent state. With
quantum enhancement we beat the CSL by approximately 15 +/- 4% and introduce a paradox where too much squeezing exists.We present theory and simulation validated by experiment for resonance enhanced
quantum smoothing. When estimating the position of a mechanically resonant cavity mirror, this technique shows a precision enhancement of greater than two compared with optimal filtering. Previously smoothing enhancement has not exceeded two.Finally, theoretical and simulation results are provided for
quantum enhanced mirror position estimation using resonant
quantum smoothing. Our results indicate precision improvement of approximately 20 +/- 4% with
quantum enhancement.
Advisors/Committee Members: Petersen, Ian, Information Technology & Electrical Engineering, UNSW Canberra, UNSW, Huntington, Elanor, Research School of Engineering, College of Engineering and Computer Science, Australian National University.
Subjects/Keywords: Quantum control; Quantum parameter estimation; Quantum optics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wheatley, T. (2016). To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/55888 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:39598/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Wheatley, Trevor. “To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing.” 2016. Doctoral Dissertation, University of New South Wales. Accessed April 18, 2021.
http://handle.unsw.edu.au/1959.4/55888 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:39598/SOURCE02?view=true.
MLA Handbook (7th Edition):
Wheatley, Trevor. “To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing.” 2016. Web. 18 Apr 2021.
Vancouver:
Wheatley T. To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing. [Internet] [Doctoral dissertation]. University of New South Wales; 2016. [cited 2021 Apr 18].
Available from: http://handle.unsw.edu.au/1959.4/55888 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:39598/SOURCE02?view=true.
Council of Science Editors:
Wheatley T. To the standard quantum limit and beyond: Experimental quantum parameter estimation using adaptive quantum smoothing. [Doctoral Dissertation]. University of New South Wales; 2016. Available from: http://handle.unsw.edu.au/1959.4/55888 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:39598/SOURCE02?view=true

Princeton University
17.
Liu, Yanbing.
Reservoir engineering in circuit quantum electrodynamics
.
Degree: PhD, 2016, Princeton University
URL: http://arks.princeton.edu/ark:/88435/dsp01mw22v794j
► Superconducting circuits have become an ideal platform to implement prototypi- cal quantum computing ideas and to study nonequilibrium quantum dynamics. This thesis covers research topics…
(more)
▼ Superconducting circuits have become an ideal platform to implement prototypi- cal
quantum computing ideas and to study nonequilibrium
quantum dynamics. This thesis covers research topics conducted in both subfields. Fast and reliable readout of volatile
quantum states is one of the key requirements to build a universal
quantum computer. In the first part, we utilize a number of techniques, ranging from a low noise amplifier to an on-chip stepped-impedance Purcell filter, to improve superconducting qubits readout fidelity. Interestingly, full
quantum theory of SIPF requires the understanding of strong coupling
quantum electrodynamics near a photonic band-gap. This problem, intimately tied to
quantum impurity problems in condensed matter physics, has never been studied experimentally prior to the development of superconducting circuits. This realization then leads to the second part, the study of atom-light interaction in structured vacuum. The word ‘structured’ means the spectral function of the vacuum is drastically different from that of free space. We directly couple a transmon qubit to a microwave photonic crystal and discuss the concepts of photon bound states and
quantum dissipative engineering in such a system. Following this research direction,
quantum electrodynamics in a driven multimode cavity, another form of structured vacuum, is also investigated both experimentally and theoretically. The most intriguing phenomenon is the multimode ultranarrow resonance fluorescence, attributed to correlated light emission.
Advisors/Committee Members: Houck, Andrew (advisor).
Subjects/Keywords: quantum computing;
quantum electrodynamics;
quantum optics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, Y. (2016). Reservoir engineering in circuit quantum electrodynamics
. (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01mw22v794j
Chicago Manual of Style (16th Edition):
Liu, Yanbing. “Reservoir engineering in circuit quantum electrodynamics
.” 2016. Doctoral Dissertation, Princeton University. Accessed April 18, 2021.
http://arks.princeton.edu/ark:/88435/dsp01mw22v794j.
MLA Handbook (7th Edition):
Liu, Yanbing. “Reservoir engineering in circuit quantum electrodynamics
.” 2016. Web. 18 Apr 2021.
Vancouver:
Liu Y. Reservoir engineering in circuit quantum electrodynamics
. [Internet] [Doctoral dissertation]. Princeton University; 2016. [cited 2021 Apr 18].
Available from: http://arks.princeton.edu/ark:/88435/dsp01mw22v794j.
Council of Science Editors:
Liu Y. Reservoir engineering in circuit quantum electrodynamics
. [Doctoral Dissertation]. Princeton University; 2016. Available from: http://arks.princeton.edu/ark:/88435/dsp01mw22v794j
18.
O'Malley, Peter James Joyce.
Superconducting Qubits: Dephasing and Quantum Chemistry.
Degree: 2016, University of California – eScholarship, University of California
URL: http://www.escholarship.org/uc/item/21x6x9tk
► One of the most exciting potential applications of a quantum computer is the abilityto efficiently simulate quantum systems, a task that is out of the…
(more)
▼ One of the most exciting potential applications of a quantum computer is the abilityto efficiently simulate quantum systems, a task that is out of the reach of even thelargest classical supercomputers. Such simulations require a quantum algorithm capableof efficiently representing and manipulating a quantum system, as well as a device withsufficient coherence to execute it. In this work, we describe experiments advancing bothof these goals. First, we discuss dephasing—currently a leading cause of decoherencein superconducting qubits—and present measurements accurately quantifying both low-and high-frequency phase noise sources. We then discuss two quantum algorithms forthe simulation of chemical Hamiltonians, and experimentally contrast their performance.These results show that with continuing improvement in quantum devices we may soonbe able to apply quantum computers to practical chemistry problems.
Subjects/Keywords: Quantum physics; Physics; Chemistry; Quantum Algorithms; Quantum Chemistry; Quantum Computation; Quantum Information; Quantum Noise
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
O'Malley, P. J. J. (2016). Superconducting Qubits: Dephasing and Quantum Chemistry. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/21x6x9tk
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
O'Malley, Peter James Joyce. “Superconducting Qubits: Dephasing and Quantum Chemistry.” 2016. Thesis, University of California – eScholarship, University of California. Accessed April 18, 2021.
http://www.escholarship.org/uc/item/21x6x9tk.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
O'Malley, Peter James Joyce. “Superconducting Qubits: Dephasing and Quantum Chemistry.” 2016. Web. 18 Apr 2021.
Vancouver:
O'Malley PJJ. Superconducting Qubits: Dephasing and Quantum Chemistry. [Internet] [Thesis]. University of California – eScholarship, University of California; 2016. [cited 2021 Apr 18].
Available from: http://www.escholarship.org/uc/item/21x6x9tk.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
O'Malley PJJ. Superconducting Qubits: Dephasing and Quantum Chemistry. [Thesis]. University of California – eScholarship, University of California; 2016. Available from: http://www.escholarship.org/uc/item/21x6x9tk
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Auckland
19.
de Oliveira, Felipe Dimer.
Study of the Dicke model: from phase space approach to quantum trajectories.
Degree: 2008, University of Auckland
URL: http://hdl.handle.net/2292/3106
► In this thesis we study the Dicke model outside the rotating wave approximation (RWA), by employing phase space techniques and the quantum trajectory theory. We…
(more)
▼ In this thesis we study the Dicke model outside the rotating wave approximation (RWA),
by employing phase space techniques and the
quantum trajectory theory. We present
a review of the basic models of open systems in
quantum optics and present an experimental
proposition justifying the model to be studied. We use the phase space approach
to study, among other subjects, entanglement, squeezing and fluctuations across a
quantum
phase transition. Three different phase space representations are used and their
strengths and weaknesses compared. The
quantum trajectory theory is applied to visualise
the global
quantum fluctuations and to learn how different measurement schemes
will affect the creation of entanglement.
Advisors/Committee Members: Prof. Howard Carmichael, Dr. Scott Parkins.
Subjects/Keywords: Superradiance; quantum noise; quantum trajectories
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
de Oliveira, F. D. (2008). Study of the Dicke model: from phase space approach to quantum trajectories. (Doctoral Dissertation). University of Auckland. Retrieved from http://hdl.handle.net/2292/3106
Chicago Manual of Style (16th Edition):
de Oliveira, Felipe Dimer. “Study of the Dicke model: from phase space approach to quantum trajectories.” 2008. Doctoral Dissertation, University of Auckland. Accessed April 18, 2021.
http://hdl.handle.net/2292/3106.
MLA Handbook (7th Edition):
de Oliveira, Felipe Dimer. “Study of the Dicke model: from phase space approach to quantum trajectories.” 2008. Web. 18 Apr 2021.
Vancouver:
de Oliveira FD. Study of the Dicke model: from phase space approach to quantum trajectories. [Internet] [Doctoral dissertation]. University of Auckland; 2008. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/2292/3106.
Council of Science Editors:
de Oliveira FD. Study of the Dicke model: from phase space approach to quantum trajectories. [Doctoral Dissertation]. University of Auckland; 2008. Available from: http://hdl.handle.net/2292/3106

University of Rochester
20.
Kinnischtzke, Laura A.
Quantum dot photonics.
Degree: PhD, 2017, University of Rochester
URL: http://hdl.handle.net/1802/33150
► We report on several experiments using single excitons conned to single semiconductor quantum dots (QDs). Electric and magnetic elds have previously been used as experimental…
(more)
▼ We report on several experiments using single
excitons conned to single semiconductor
quantum dots (QDs).
Electric and magnetic elds have previously been used
as
experimental knobs to understand and control individual excitons in
single quantum
dots. We realize new ways of electric eld control
by changing materials and
device geometry in the rst two
experiments with strain-based InAs QDs. A standard
Schottky diode
heterostructure is demonstrated with graphene as the Schottky
gate
material, and its performance is bench-marked against a diode with
a standard
gate material, semi-transparent nickel-chromium (NiCr).
This change of materials
increases the photon collection rate by
eliminating absorption in the metallic NiCr
layer. A second set of
experiments investigates the electric eld response of QDs
as a
possible metrology source. A linear voltage potential drop in a
plane near the
QDs is used to describe how the spatially varying
voltage prole is also imparted on
the QDs. We demonstrate a
procedure to map this voltage prole as a preliminary
route towards
a full quantum sensor array. Lastly, InAs QDs are explored as
potential
spin-photon interfaces. We describe how a magnetic eld
is used to realize a
reversible exchange of information between
light and matter, including a discussion of
the
polarization-dependence of the photoluminesence, and how that can
be linked to
the spin of a resident electron or hole. We present
evidence of this in two wavelength
regimes for InAs quantum dots,
and discuss how an external magnetic field informs
the spin
physics of these 2-level systems. This thesis concludes with the
discovery of
a new class of quantum dots. As-yet unidentied defect
states in single layer tungsten
diselenide (WSe2) are shown to
host quantum light emission. We explore the spatial
extent of
electron connement and tentatively identify a radiative lifetime of
~1 ns
for these single photon emitters.
Subjects/Keywords: Quantum dots; Quantum optics; Photonics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kinnischtzke, L. A. (2017). Quantum dot photonics. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/33150
Chicago Manual of Style (16th Edition):
Kinnischtzke, Laura A. “Quantum dot photonics.” 2017. Doctoral Dissertation, University of Rochester. Accessed April 18, 2021.
http://hdl.handle.net/1802/33150.
MLA Handbook (7th Edition):
Kinnischtzke, Laura A. “Quantum dot photonics.” 2017. Web. 18 Apr 2021.
Vancouver:
Kinnischtzke LA. Quantum dot photonics. [Internet] [Doctoral dissertation]. University of Rochester; 2017. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1802/33150.
Council of Science Editors:
Kinnischtzke LA. Quantum dot photonics. [Doctoral Dissertation]. University of Rochester; 2017. Available from: http://hdl.handle.net/1802/33150
21.
Fan, Weikang.
Design and fabrication of ion traps for a scalable microwave quantum computer.
Degree: PhD, 2020, University of Sussex
URL: http://sro.sussex.ac.uk/id/eprint/89329/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801039
► This thesis describes the experimental work towards the development of a scalable quantum computer based on microfabricated ion trap using long-wavelength radiation and magnetic field…
(more)
▼ This thesis describes the experimental work towards the development of a scalable quantum computer based on microfabricated ion trap using long-wavelength radiation and magnetic field gradient. There are three key elements in implementing such a quantum computer: the junction trap to shuttle ions, the structure to generate high gradient magnetic field and the structure to induce strong microwave coupling to the ions. A new dynamic simulation tool was developed addressing the problems faced by static solvers. This tool was used to aid the design and optimisation of an X junction geometry allowing the ions to be shuttled with minimised motional heating gain. The design and fabrication techniques were reported on the structure to generate a high gradient magnetic field. A discussion was given on the design of producing microwave and maximise the coupling to the cold ions. A review was given on the far-field methods and near-field methods. A novel design was reported where the single-qubit gate is predicted to be 45 times faster than a conventional setup. Two essential topics on the microfabrication of a reliable scalable quantum computer unit were discussed: breakdown and RF loss. Investigation using numerical simulations showed that dielectric can breakdown due to high voltage and local heating which are results of impedance mismatch. Microfabrication processes were improved, high-quality films were reported to have twice as much breakdown voltages. The mechanisms of RF loss were reviewed. Novel structures and smooth electroplating technique were developed to minimise the loss. A low loss ion trap was produced and tested. An experimentally observed anomalous glow discharge phenomenon was reported and investigated.
Subjects/Keywords: QC0174.12 Quantum theory. Quantum mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fan, W. (2020). Design and fabrication of ion traps for a scalable microwave quantum computer. (Doctoral Dissertation). University of Sussex. Retrieved from http://sro.sussex.ac.uk/id/eprint/89329/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801039
Chicago Manual of Style (16th Edition):
Fan, Weikang. “Design and fabrication of ion traps for a scalable microwave quantum computer.” 2020. Doctoral Dissertation, University of Sussex. Accessed April 18, 2021.
http://sro.sussex.ac.uk/id/eprint/89329/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801039.
MLA Handbook (7th Edition):
Fan, Weikang. “Design and fabrication of ion traps for a scalable microwave quantum computer.” 2020. Web. 18 Apr 2021.
Vancouver:
Fan W. Design and fabrication of ion traps for a scalable microwave quantum computer. [Internet] [Doctoral dissertation]. University of Sussex; 2020. [cited 2021 Apr 18].
Available from: http://sro.sussex.ac.uk/id/eprint/89329/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801039.
Council of Science Editors:
Fan W. Design and fabrication of ion traps for a scalable microwave quantum computer. [Doctoral Dissertation]. University of Sussex; 2020. Available from: http://sro.sussex.ac.uk/id/eprint/89329/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801039
22.
Rubio Jiménez, Jesús.
Non-asymptotic quantum metrology : extracting maximum information from limited data.
Degree: PhD, 2020, University of Sussex
URL: http://sro.sussex.ac.uk/id/eprint/89459/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801042
► Science relies on our practical ability to extract information from reality, since processing this information is essential for developing theories that explain our world. This…
(more)
▼ Science relies on our practical ability to extract information from reality, since processing this information is essential for developing theories that explain our world. This thesis is precisely the study of how to extract and process information using quantum systems when a constrained amount of resources means that the available data is limited. The natural framework for this task is quantum metrology, a set of tools to model and design quantum measurement strategies. Equipped with this theory, we advocate a Bayesian approach as the appropriate formalism to study systems with a finite amount of resources, which is a non-asymptotic problem, and we propose a methodology for non-asymptotic quantum metrology. To start with, we show the consistency of taking those solutions that are optimal in the asymptotic regime of many trials as a guide to calculate a generalised measure of uncertainty in the Bayesian framework. This provides an approximate but useful way of studying the non-asymptotic regime whenever a direct Bayesian optimisation is intractable, and it avoids non-physical results that can arise when only the asymptotic theory is employed. Secondly, we construct a new non-asymptotic Bayesian bound without relying on the previous approximation by first selecting the optimal quantum strategy for a single shot, and then simulating a sequence of repetitions of this scheme, which is suitable for experiments where we do not wish or cannot correlate different trials. These methods are applied to a Mach-Zehnder interferometer, which is a single-parameter problem, and to quantum sensing networks where the nodes are either qubits or optical modes, which are multi-parameter protocols. Our results provide a detailed characterisation of how the interplay between prior information, entanglement and a limited amount of data affects the performance of quantum metrology protocols, which has important implications for the analysis of theory and experiments in this field.
Subjects/Keywords: QC0174.12 Quantum theory. Quantum mechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rubio Jiménez, J. (2020). Non-asymptotic quantum metrology : extracting maximum information from limited data. (Doctoral Dissertation). University of Sussex. Retrieved from http://sro.sussex.ac.uk/id/eprint/89459/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801042
Chicago Manual of Style (16th Edition):
Rubio Jiménez, Jesús. “Non-asymptotic quantum metrology : extracting maximum information from limited data.” 2020. Doctoral Dissertation, University of Sussex. Accessed April 18, 2021.
http://sro.sussex.ac.uk/id/eprint/89459/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801042.
MLA Handbook (7th Edition):
Rubio Jiménez, Jesús. “Non-asymptotic quantum metrology : extracting maximum information from limited data.” 2020. Web. 18 Apr 2021.
Vancouver:
Rubio Jiménez J. Non-asymptotic quantum metrology : extracting maximum information from limited data. [Internet] [Doctoral dissertation]. University of Sussex; 2020. [cited 2021 Apr 18].
Available from: http://sro.sussex.ac.uk/id/eprint/89459/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801042.
Council of Science Editors:
Rubio Jiménez J. Non-asymptotic quantum metrology : extracting maximum information from limited data. [Doctoral Dissertation]. University of Sussex; 2020. Available from: http://sro.sussex.ac.uk/id/eprint/89459/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.801042

Texas A&M University
23.
Asiri, Saeed Mater M.
Quantum State Reconstruction in Quantum Optomechanics.
Degree: PhD, Physics, 2018, Texas A&M University
URL: http://hdl.handle.net/1969.1/174171
► The ability to perform mechanical states reconstruction is an essential task in quantum optomechanics to understand different quantum aspects of mechanical states of motion. Many…
(more)
▼ The ability to perform mechanical states reconstruction is an essential task in
quantum optomechanics
to understand different
quantum aspects of mechanical states of motion. Many interesting
phenomena appear when the light and mechanical motion are coupled through the radiationpressure
coupling. Preparing, controlling, and measuring mechanical states are all very crucial in
the study and development of
quantum optomechanics. In this dissertation, we introduce a practical
scheme for mechanical states reconstruction in the weak optomechancial coupling regime in
which most optomechanical systems operates. The scheme relies on sending a beam of two-level
atoms to pass through an optomechanical cavity where an oscillating mirror is coupled to a cavity
field. The atoms interact resonantly with the cavity field as they pass through the cavity. As the
oscillating mirror modifies the dynamics of the atoms, we show in this dissertation that by measuring
the atomic population inversion of the atoms when they exit the optomechanical cavity, it is
possible to obtain the mirror’s state by analyzing the measured data of the population inversion.
In the first part of this dissertation, we study a hybrid system in which a two-level atom is
placed inside a cavity field where one side of the cavity is free to move. The two-level atom
is coupled to the cavity field through the well known Jaynes-Cummings coupling, whereas the
mechanical mirror and the cavity field are coupled to each other via the radiation-pressure coupling.
A complete analytical and numerical study is performed on this system, and it is shown that the
mechanical mirror modifies the atomic population inversion in such a way that each mechanical
state changes the signal of the population inversion of the atom differently. From the results in this
part of the dissertation, we concluded that the population inversion can be analyzed and employed
to extract the
quantum state of the mechanical mirror.
Second, as each specific mechanical state affects the atomic population inversion differently,
we developed the idea of using the atom as a tool to reconstruct the
quantum state of the mechanical
mirror. We first assumed that the two-level atom is initially in a superposition of its excited
and ground states while both the cavity field and the mechanical mirror are in general superposiii
tion of Fock states with unknown coefficients. The derived general expression of the population
inversion indicates that it is sufficient to initially prepare the atoms in the excited states before
passing through the optomechancial cavity and the cavity field is in vacuum state. The population
inversion of the atoms exiting the cavity can then be measured, and the collected data can be used
to determine the full state of the mechanical mirror. The scheme in this part of the dissertation is
only developed for measuring pure mechanical states.
Third, we extended the scheme of mechanical states reconstruction to the more practical states
of the mirror in which the mirror is initially in a mixed…
Advisors/Committee Members: Zubairy, M. Suhail (advisor), Hemmer, Philip (committee member), Kocharovskaya, Olga (committee member), Zheltikov, Aleksei (committee member).
Subjects/Keywords: Quantum optics; Quantum optomechanics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Asiri, S. M. M. (2018). Quantum State Reconstruction in Quantum Optomechanics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174171
Chicago Manual of Style (16th Edition):
Asiri, Saeed Mater M. “Quantum State Reconstruction in Quantum Optomechanics.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 18, 2021.
http://hdl.handle.net/1969.1/174171.
MLA Handbook (7th Edition):
Asiri, Saeed Mater M. “Quantum State Reconstruction in Quantum Optomechanics.” 2018. Web. 18 Apr 2021.
Vancouver:
Asiri SMM. Quantum State Reconstruction in Quantum Optomechanics. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/1969.1/174171.
Council of Science Editors:
Asiri SMM. Quantum State Reconstruction in Quantum Optomechanics. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174171

McMaster University
24.
Safari, Akbar.
Some Recent Developments in WKB Approximation.
Degree: MSc, 2013, McMaster University
URL: http://hdl.handle.net/11375/13351
► WKB theory provides a plausible link between classical mechanics and quantum mechanics in its semi-classical limit. Connecting the WKB wave function across the turning…
(more)
▼ WKB theory provides a plausible link between classical mechanics and quantum mechanics in its semi-classical limit. Connecting the WKB wave function across the turning points in a quantum well, leads to the WKB quantization condition. In this work, I focus on some improvements and recent developments related to the WKB quantization condition. First I discuss how the combination of super-symmetric quantum mechanics and WKB, gives the SWKB quantization condition which is exact for a large class of potentials called shape invariant potentials. Next I turn to the fact that there is always a probability of refection when the potential is not constant and the phase of the wave function should account for this refection. WKB theory ignores refection except at turning points. I explain the work of Friedrich and Trost who showed that by including the correct "refection phase" at a turning point, the WKB quantization condition can be made to give exact bound state energies. Next I discuss the work of Cao and collaborators which takes refection of the wave function into account everywhere. We show that Cao's method provides a way to compute the F-T refection phase. Finally I discuss a paper of Fabre and Guery-Odelin who used the exponential potential to study the accuracy of WKB. In their results the accuracy deteriorates as the energy increases, which is inconsistent with Bohr's correspondence principle. Using the Friedrich and Trost method, we resolved this problem.
Master of Science (MSc)
Advisors/Committee Members: Sprung, Donald, Physics and Astronomy.
Subjects/Keywords: Quantum Physics; Quantum Physics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Safari, A. (2013). Some Recent Developments in WKB Approximation. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/13351
Chicago Manual of Style (16th Edition):
Safari, Akbar. “Some Recent Developments in WKB Approximation.” 2013. Masters Thesis, McMaster University. Accessed April 18, 2021.
http://hdl.handle.net/11375/13351.
MLA Handbook (7th Edition):
Safari, Akbar. “Some Recent Developments in WKB Approximation.” 2013. Web. 18 Apr 2021.
Vancouver:
Safari A. Some Recent Developments in WKB Approximation. [Internet] [Masters thesis]. McMaster University; 2013. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/11375/13351.
Council of Science Editors:
Safari A. Some Recent Developments in WKB Approximation. [Masters Thesis]. McMaster University; 2013. Available from: http://hdl.handle.net/11375/13351

University of Waterloo
25.
Alexander, Matthew.
A Polar Decomposition for Quantum Channels: Theory and Applications.
Degree: 2019, University of Waterloo
URL: http://hdl.handle.net/10012/14931
► Every potential benefit of quantum computers would be lost without methods to protect the computations from error. Quantum channels provide a framework for understanding error…
(more)
▼ Every potential benefit of quantum computers would be lost without methods to protect the computations from error. Quantum channels provide a framework for understanding error in quantum systems. In general, for a system of size d, a quantum channel may require as many as ~d4 parameters to characterize it. We introduce the leading Kraus approximation, a simplification which reduces the number of parameters to ~d2, while accurately approximating two figures of merit important to the experimentalist: the unitarity and average process fidelity. Additionally, applying the leading Kraus approximation declutters investigations into the set of quantum channels. When applied, a natural decomposition of channels arises, separating behaviour into coherent and decoherent contributions. We find that eliminating the coherent contribution provides the greatest increase to the fidelity, while decoherent processes provide a generalization of depolarizing channels.
Subjects/Keywords: quantum theory; quantum computers
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alexander, M. (2019). A Polar Decomposition for Quantum Channels: Theory and Applications. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/14931
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Alexander, Matthew. “A Polar Decomposition for Quantum Channels: Theory and Applications.” 2019. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/14931.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Alexander, Matthew. “A Polar Decomposition for Quantum Channels: Theory and Applications.” 2019. Web. 18 Apr 2021.
Vancouver:
Alexander M. A Polar Decomposition for Quantum Channels: Theory and Applications. [Internet] [Thesis]. University of Waterloo; 2019. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/14931.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Alexander M. A Polar Decomposition for Quantum Channels: Theory and Applications. [Thesis]. University of Waterloo; 2019. Available from: http://hdl.handle.net/10012/14931
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
26.
Onuma-Kalu, Marvellous.
Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions.
Degree: 2020, University of Waterloo
URL: http://hdl.handle.net/10012/15540
► This thesis has two parts; the first part is a contribution to the research field of quantum measurement in quantum optics while the second part…
(more)
▼ This thesis has two parts; the first part is a contribution to the research field of quantum measurement in quantum optics while the second part focuses on quantum thermodynamics for fermionic systems.
The aim of the research on quantum optics is to detect and subsequently characterize quantum states of light. Specifically, we focus on characterizing 1) entanglement between a two-level atom and superposition of coherent states (known as Bell cat state) 2) quantum superposition of coherent states (Schrödinger cat states). The photon is the particle of light which carries quantum information; it is usually lost (destroyed) while being detected. Many physical implementations of quantum logic gate aim to encode quantum information processing into large registers of entangled qubits. However for these larger much distinguishable states, creating and preserving entanglement becomes difficult due to rapid onset of decoherence. Encoding quantum information on Schrodinger's cat states take advantage of a cavity resonators much larger Hilbert space, as compared with that of a two-level system. This architecture allows redundant qubit encodings that can simplify the operations needed to initialize, manipulate and measure the encoded information. For such a system to be viable as a quantum computing platform, efficient measurement of such encoded qubit observables must be possible.
The concept of quantum non demolition measurement was introduced to evade the problem of decoherence. Researchers now know through quantum theory that it is indeed possible to count photons in a given state of light without destroying them. This nondestructive measurement scheme is coined in the term ``quantum non-demolition measurement". We can extend the ideas of quantum nondemolition measurement scheme to detect a system made up of two or more quantum states (not necessarily states of light) that are combined based on the superposition principle. An example is the Schrödinger's cat state which is a superposition of two coherent states of light of equal amplitudes but opposite phase. At this point, one is not only interested in counting photons, but in understanding the nature of the superposition, the possible problems and the different physical properties that follow. Ways to detect the Schrödinger cat states and subsequently a Bell cat state (Schrödinger cat entangled with a qubit) without significantly perturbing them are discussed. The method analyzed is the mode-invisibility measurement scheme earlier proposed to detect single Fock states and coherent states of light. The method gives a new insight to the known properties of Schrödinger cat states and contributes to our understanding of the quantum-classical boundary problem.
The second part of the thesis falls in the research field of quantum thermodynamics and open quantum systems. Most problems in quantum thermodynamics have been explored in bosonic systems with little or less done in fermionic systems. Therefore the aim of this part of the thesis is to explore related…
Subjects/Keywords: Quantum computing; Quantum theory; Fermions
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Onuma-Kalu, M. (2020). Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Onuma-Kalu, Marvellous. “Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions.” 2020. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/15540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Onuma-Kalu, Marvellous. “Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions.” 2020. Web. 18 Apr 2021.
Vancouver:
Onuma-Kalu M. Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/15540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Onuma-Kalu M. Exploring new routes to decoherence-free quantum computing; and quantum thermodynamics for fermions. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/15540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
27.
Mastromattei, Christian.
Assessing the Practicality of a Simple Multi-node Quantum Repeater.
Degree: 2017, University of Waterloo
URL: http://hdl.handle.net/10012/12590
► This thesis assesses the theoretical performance of a realistic multi-node quantum repeater that is implementable with current technology. A quantum repeater, by definition, allows for…
(more)
▼ This thesis assesses the theoretical performance of a realistic multi-node quantum repeater that is implementable with current technology. A quantum repeater, by definition, allows for communication rates in a channel to be larger than what is fundamentally possible over a loss only channel. We consider a simple, one-way, multi-node quantum repeater that utilizes entanglement swapping in the absence of any quantum error correction or entanglement purification. We create a theoretical model of the quantum repeater, incorporating the imperfections of each component within the system, to get an accurate key rate using current, viable state-of-the-art experimental parameters. Our main goal is to benchmark the performance of this specific multi-node quantum repeater. We compare the performance of this multi-node system to that of a single node repeater, which has been previously analysed for this architecture. We are interested to see if there is an advantage for introducing more nodes in this type of system. We also provide some suggestions for improving the key rate performance.
Subjects/Keywords: quantum repeater; quantum key distribution
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mastromattei, C. (2017). Assessing the Practicality of a Simple Multi-node Quantum Repeater. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/12590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mastromattei, Christian. “Assessing the Practicality of a Simple Multi-node Quantum Repeater.” 2017. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/12590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mastromattei, Christian. “Assessing the Practicality of a Simple Multi-node Quantum Repeater.” 2017. Web. 18 Apr 2021.
Vancouver:
Mastromattei C. Assessing the Practicality of a Simple Multi-node Quantum Repeater. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/12590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mastromattei C. Assessing the Practicality of a Simple Multi-node Quantum Repeater. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/12590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of KwaZulu-Natal
28.
Mpofu, Kelvin Tafadzwa.
Quantum analogues of classical optimization algorithms.
Degree: 2017, University of KwaZulu-Natal
URL: http://hdl.handle.net/10413/15712
► This thesis explores the quantum analogues of algorithms used in mathematical optimization. The thesis focuses primarily on the iterative gradient search algorithm (algorithm for finding…
(more)
▼ This thesis explores the
quantum analogues of algorithms used in mathematical optimization.
The thesis focuses primarily on the iterative gradient search algorithm (algorithm
for finding the minimum or maximum of a function) and the Newton-Raphson
algorithm. The thesis introduces a new
quantum gradient algorithm suggested by
Professor Thomas Konrad and colleagues and a
quantum analogue of the Newton-Raphson
Method, a method for finding approximations to the roots or zeroes of a real-valued function.
The
quantum gradient algorithm and the
quantum Newton-Raphson are shown to
give a polynomial speed up over their classical analogues.
Advisors/Committee Members: Konrad, Thomas. (advisor), Tame, Mark. (advisor).
Subjects/Keywords: Quantum optimization.; Quantum algorithms.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mpofu, K. T. (2017). Quantum analogues of classical optimization algorithms. (Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/15712
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mpofu, Kelvin Tafadzwa. “Quantum analogues of classical optimization algorithms.” 2017. Thesis, University of KwaZulu-Natal. Accessed April 18, 2021.
http://hdl.handle.net/10413/15712.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mpofu, Kelvin Tafadzwa. “Quantum analogues of classical optimization algorithms.” 2017. Web. 18 Apr 2021.
Vancouver:
Mpofu KT. Quantum analogues of classical optimization algorithms. [Internet] [Thesis]. University of KwaZulu-Natal; 2017. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10413/15712.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mpofu KT. Quantum analogues of classical optimization algorithms. [Thesis]. University of KwaZulu-Natal; 2017. Available from: http://hdl.handle.net/10413/15712
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
29.
Pitalúa-García, Damián.
Quantum information, Bell inequalities and the no-signalling principle.
Degree: PhD, 2014, University of Cambridge
URL: https://doi.org/10.17863/CAM.16129
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600535
► This PhD thesis contains a general introduction and three main chapters. Chapter 2 investigates Bell inequalities that generalize the CHSH and Braunstein-Caves inequalities. Chapter 3…
(more)
▼ This PhD thesis contains a general introduction and three main chapters. Chapter 2 investigates Bell inequalities that generalize the CHSH and Braunstein-Caves inequalities. Chapter 3 shows a derivation of an upper bound on the success probability of a class of quantum teleportation protocols, denoted as port-based teleportation, from the no-cloning theorem and the no-signalling principle. Chapter 4 introduces the principle of quantum information causality. Chapter 2 considers the predictions of quantum theory and local hidden variable theories (LHVT) for the correlations obtained by measuring a pair of qubits by projections defined by randomly chosen axes separated by a given angle θ. The predictions of LHVT correspond to binary colourings of the Bloch sphere with antipodal points oppositely coloured. We show a Bell inequality for all θ, which generalizes the CHSH and the Braunstein-Caves inequalities in the sense that the measurement choices are not restricted to be in a finite set, but are constrained only by the angle θ. We motivate and explore the hypothesis that for a continuous range of θ > 0, the maximum correlation (anticorrelation) is obtained by assigning to one qubit the colouring with one hemisphere black and the other white, and assigning the same (reverse) colouring to the other qubit. We describe numerical tests that are consistent with this hypothesis and bound the range of θ. Chapter 3 shows a derivation of an upper bound on the success probability of port-based teleportation from the no-cloning theorem and the no-signalling principle. Chapter 4 introduces the principle of quantum information causality, a quantum version of the information causality principle. The quantum information causality principle states the maximum amount of quantum information that a transmitted quantum system can communicate as a function of its dimension, independently of any quantum physical resources previously shared by the communicating parties. These principles reduce to the no-signalling principle if no systems are transmitted. We present a new quantum information task, the quantum information causality game, whose success probability is upper bounded by the new principle, and show that an optimal strategy to perform it combines the quantum teleportation and superdense coding protocols with a task that has classical inputs.
Subjects/Keywords: 530.12; Quantum information; Quantum foundations
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pitalúa-García, D. (2014). Quantum information, Bell inequalities and the no-signalling principle. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.16129 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600535
Chicago Manual of Style (16th Edition):
Pitalúa-García, Damián. “Quantum information, Bell inequalities and the no-signalling principle.” 2014. Doctoral Dissertation, University of Cambridge. Accessed April 18, 2021.
https://doi.org/10.17863/CAM.16129 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600535.
MLA Handbook (7th Edition):
Pitalúa-García, Damián. “Quantum information, Bell inequalities and the no-signalling principle.” 2014. Web. 18 Apr 2021.
Vancouver:
Pitalúa-García D. Quantum information, Bell inequalities and the no-signalling principle. [Internet] [Doctoral dissertation]. University of Cambridge; 2014. [cited 2021 Apr 18].
Available from: https://doi.org/10.17863/CAM.16129 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600535.
Council of Science Editors:
Pitalúa-García D. Quantum information, Bell inequalities and the no-signalling principle. [Doctoral Dissertation]. University of Cambridge; 2014. Available from: https://doi.org/10.17863/CAM.16129 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600535

Boston College
30.
Ye, Bing.
Unconventional Quantum Phases in Strongly Correlated
Systems.
Degree: PhD, Physics, 2016, Boston College
URL: http://dlib.bc.edu/islandora/object/bc-ir:106990
► In this thesis, I investigated and implemented various numerical and simulation methods, including mean field theory, functional renormalization group method (fRG), density matrix renormalization group…
(more)
▼ In this thesis, I investigated and implemented various
numerical and simulation methods, including mean field theory,
functional renormalization group method (fRG), density matrix
renormalization group (DMRG) method etc., to find different
quantum
phases and
quantum phase diagrams on models of correlated
electronic systems. I found different phase diagrams with phases
such as magnetism, superconductivity. By summarizing the strength
and limitations of these methods, I investigated the projected
entangled paired states (PEPS) with symmetry
quantum number to
sharply distinguish phases into crude classes and applied a
variation of fast full update (FFU) prototype[58] to simulate
different phases numerically. This method provides a promising,
powerful and efficient way to simulate unconventional
quantum
phases and
quantum phase diagrams in correlated electronic
systems.
Advisors/Committee Members: Ying Ran (Thesis advisor).
Subjects/Keywords: Quantum phases; Quantum phase diagrams
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ye, B. (2016). Unconventional Quantum Phases in Strongly Correlated
Systems. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:106990
Chicago Manual of Style (16th Edition):
Ye, Bing. “Unconventional Quantum Phases in Strongly Correlated
Systems.” 2016. Doctoral Dissertation, Boston College. Accessed April 18, 2021.
http://dlib.bc.edu/islandora/object/bc-ir:106990.
MLA Handbook (7th Edition):
Ye, Bing. “Unconventional Quantum Phases in Strongly Correlated
Systems.” 2016. Web. 18 Apr 2021.
Vancouver:
Ye B. Unconventional Quantum Phases in Strongly Correlated
Systems. [Internet] [Doctoral dissertation]. Boston College; 2016. [cited 2021 Apr 18].
Available from: http://dlib.bc.edu/islandora/object/bc-ir:106990.
Council of Science Editors:
Ye B. Unconventional Quantum Phases in Strongly Correlated
Systems. [Doctoral Dissertation]. Boston College; 2016. Available from: http://dlib.bc.edu/islandora/object/bc-ir:106990
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