subject:(quantum computing)

University of Melbourne

1. Wang, David. Topological quantum error correction and quantum algorithm simulations.

Degree: 2011, University of Melbourne

► Quantum computers are machines that manipulate quantum information stored in the form of qubits, the quantum analogue to the classical bit. Unlike the bit, quantum… (more)

▼ Quantum computers are machines that manipulate quantum information stored in the form of qubits, the quantum analogue to the classical bit. Unlike the bit, quantum mechanics allows a qubit to be in a linear superposition of both its basis states. Given the same number of bits and qubits, the latter stores exponentially more information. Quantum algorithms exploit these superposition states, allowing quantum computers to solve problems such as prime number factorisation and searches faster than classical computers. Realising a large-scale quantum computer is difficult because quantum information is highly susceptible to noise. Error correction may be employed to suppress the noise, so that the results of large quantum algorithms are valid. The overhead incurred from introducing error correction is neutralised if all elementary quantum operations are constructed with an error rate below some threshold error rate. Below threshold, arbitrary length quantum computation is possible. We investigate two topological quantum error correcting codes, the planar code and the 2D colour code. We find the threshold for the 2D colour code to be 0.1%, and improve the planar code threshold from 0.75% to 1.1%. Existing protocols for the transmission of quantum states are hindered by maximum communication distances and low communication rates. We adapt the planar code for use in quantum communication, and show that this allows the fault-tolerant transmission of quantum information over arbitrary distances at a rate limited only by local quantum gate speed. Error correction is an expensive investment and thus one seeks to employ as little as possible without compromising the integrity of the results. It is therefore important to study the robustness of algorithms to noise. We show that using the matrix product state representation allows one to simulate far larger instances of the quantum factoring algorithm than under the traditional amplitude formalism representation. We simulate systems with as many as 42 qubits on a single processor with 32GB RAM, comparable to amplitude formalism simulations performed on far larger computers.

Subjects/Keywords: quantum computing

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APA (6^th Edition):

Wang, D. (2011). Topological quantum error correction and quantum algorithm simulations. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/36984

Chicago Manual of Style (16^th Edition):

Wang, David. “Topological quantum error correction and quantum algorithm simulations.” 2011. Doctoral Dissertation, University of Melbourne. Accessed November 20, 2019. http://hdl.handle.net/11343/36984.

MLA Handbook (7^th Edition):

Wang, David. “Topological quantum error correction and quantum algorithm simulations.” 2011. Web. 20 Nov 2019.

Vancouver:

Wang D. Topological quantum error correction and quantum algorithm simulations. [Internet] [Doctoral dissertation]. University of Melbourne; 2011. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/11343/36984.

Council of Science Editors:

Wang D. Topological quantum error correction and quantum algorithm simulations. [Doctoral Dissertation]. University of Melbourne; 2011. Available from: http://hdl.handle.net/11343/36984

University of Washington

2. Crosson, Elizabeth. Classical and Quantum Computation in Ground States and Beyond.

Degree: PhD, 2015, University of Washington

URL: http://hdl.handle.net/1773/34128

► In this dissertation we study classical and quantum spin systems with applications to the theory of computation. In particular, we examine computational aspects of these… (more)

Subjects/Keywords: Quantum Computing; Quantum physics; physics

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APA (6^th Edition):

Crosson, E. (2015). Classical and Quantum Computation in Ground States and Beyond. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/34128

Chicago Manual of Style (16^th Edition):

Crosson, Elizabeth. “Classical and Quantum Computation in Ground States and Beyond.” 2015. Doctoral Dissertation, University of Washington. Accessed November 20, 2019. http://hdl.handle.net/1773/34128.

MLA Handbook (7^th Edition):

Crosson, Elizabeth. “Classical and Quantum Computation in Ground States and Beyond.” 2015. Web. 20 Nov 2019.

Vancouver:

Crosson E. Classical and Quantum Computation in Ground States and Beyond. [Internet] [Doctoral dissertation]. University of Washington; 2015. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1773/34128.

Council of Science Editors:

Crosson E. Classical and Quantum Computation in Ground States and Beyond. [Doctoral Dissertation]. University of Washington; 2015. Available from: http://hdl.handle.net/1773/34128

University of Waterloo

3. Govia, Luke Colin Gene. Theory and Applications of Josephson Photomultipliers.

Degree: 2012, University of Waterloo

URL: http://hdl.handle.net/10012/6971

► This thesis describes the back action of microwave-photon detection via a Josephson photomultiplier (JPM), a superconducting qubit coupled strongly to a high-quality mi- crowave cavity,… (more)

Subjects/Keywords: Quantum Information; Quantum Computing

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APA (6^th Edition):

Govia, L. C. G. (2012). Theory and Applications of Josephson Photomultipliers. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/6971

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Govia, Luke Colin Gene. “Theory and Applications of Josephson Photomultipliers.” 2012. Thesis, University of Waterloo. Accessed November 20, 2019. http://hdl.handle.net/10012/6971.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Govia, Luke Colin Gene. “Theory and Applications of Josephson Photomultipliers.” 2012. Web. 20 Nov 2019.

Vancouver:

Govia LCG. Theory and Applications of Josephson Photomultipliers. [Internet] [Thesis]. University of Waterloo; 2012. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10012/6971.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Govia LCG. Theory and Applications of Josephson Photomultipliers. [Thesis]. University of Waterloo; 2012. Available from: http://hdl.handle.net/10012/6971

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Guelph

4. Majidy, Shayan. The implementation of hybrid codes and nuclear magnetic resonance quantum information processing .

Degree: 2017, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/11957

► The development of quantum error correcting techniques is of paramount importance to the ultimate goal of implementing practical quantum computers. The simultaneous transmission of quantum… (more)

Subjects/Keywords: Quantum Computing; Quantum Error Correction

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APA (6^th Edition):

Majidy, S. (2017). The implementation of hybrid codes and nuclear magnetic resonance quantum information processing . (Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/11957

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Majidy, Shayan. “The implementation of hybrid codes and nuclear magnetic resonance quantum information processing .” 2017. Thesis, University of Guelph. Accessed November 20, 2019. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/11957.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Majidy, Shayan. “The implementation of hybrid codes and nuclear magnetic resonance quantum information processing .” 2017. Web. 20 Nov 2019.

Vancouver:

Majidy S. The implementation of hybrid codes and nuclear magnetic resonance quantum information processing . [Internet] [Thesis]. University of Guelph; 2017. [cited 2019 Nov 20]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/11957.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Majidy S. The implementation of hybrid codes and nuclear magnetic resonance quantum information processing . [Thesis]. University of Guelph; 2017. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/11957

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Dalhousie University

5. Yousefabadi, Navid. OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION.

Degree: MS, Department of Physics & Atmospheric Science, 2011, Dalhousie University

URL: http://hdl.handle.net/10222/14381

► Shor’s algorithm shows that circuit-model quantum computers can factorize integers in polynomial time – exponentially more efficiently than classical computers. There is currently no analogous… (more)

Subjects/Keywords: Adiabatic Quantum Computing

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APA (6^th Edition):

Yousefabadi, N. (2011). OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14381

Chicago Manual of Style (16^th Edition):

Yousefabadi, Navid. “OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION.” 2011. Masters Thesis, Dalhousie University. Accessed November 20, 2019. http://hdl.handle.net/10222/14381.

MLA Handbook (7^th Edition):

Yousefabadi, Navid. “OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION.” 2011. Web. 20 Nov 2019.

Vancouver:

Yousefabadi N. OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10222/14381.

Council of Science Editors:

Yousefabadi N. OPTIMAL ANNEALING PATHS FOR ADIABATIC QUANTUM COMPUTATION. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14381

Dalhousie University

6. Snow-Kropla, Elliot. COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER.

Degree: MS, Department of Physics & Atmospheric Science, 2014, Dalhousie University

URL: http://hdl.handle.net/10222/53780

► A method for compiling programs for adiabatic quantum computers is described, and the resulting programs evaluated on a physically implemented adiabatic quantum machine. These results… (more)

Subjects/Keywords: Physics; Quantum Computing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Snow-Kropla, E. (2014). COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/53780

Chicago Manual of Style (16^th Edition):

Snow-Kropla, Elliot. “COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER.” 2014. Masters Thesis, Dalhousie University. Accessed November 20, 2019. http://hdl.handle.net/10222/53780.

MLA Handbook (7^th Edition):

Snow-Kropla, Elliot. “COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER.” 2014. Web. 20 Nov 2019.

Vancouver:

Snow-Kropla E. COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER. [Internet] [Masters thesis]. Dalhousie University; 2014. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10222/53780.

Council of Science Editors:

Snow-Kropla E. COMPILING PROGRAMS FOR AN ADIABATIC QUANTUM COMPUTER. [Masters Thesis]. Dalhousie University; 2014. Available from: http://hdl.handle.net/10222/53780

University of Edinburgh

7. Pius, Einar. Parallel quantum computing : from theory to practice.

Degree: PhD, 2015, University of Edinburgh

URL: http://hdl.handle.net/1842/15857

► The term quantum parallelism is commonly used to refer to a property of quantum computations where an algorithm can act simultaneously on a superposition of… (more)

▼ The term quantum parallelism is commonly used to refer to a property of quantum computations where an algorithm can act simultaneously on a superposition of states. However, this is not the only aspect of parallelism in quantum computing. Analogously to the classical computing model, every algorithm consists of elementary quantum operations and the application of them could be parallelised itself. This kind of parallelism is explored in this thesis in the one way quantum computing (1WQC) and the quantum circuit model. In the quantum circuit model we explore arithmetic circuits and circuit complexity theory. Two new arithmetic circuits for quantum computers are introduced in this work: an adder and a multiply-adder. The latter is especially interesting because its depth (i.e. the number of parallel steps required to finish the computation) is smaller than for any known classical circuit when applied sequentially. From the complexity theoretical perspective we concentrate on the classes QAC0 and QAC0[2], the quantum counterparts of AC0 and AC0[2]. The class AC0 comprises of constant depth circuits with unbounded fan-in AND and OR gates and AC0[2] is obtained when unbounded fan-in parity gates are added to AC0 circuits. We prove that QAC0 circuits with two layers of multi-qubit gates cannot compute parity exactly. This is a step towards proving QAC0 6= QAC0[2], a relation known to hold for AC0 and AC0[2]. In 1WQC, computation is done through measurements on an entangled state called the resource state. Two well known parallelisation methods exist in this model: signal shifting and finding the maximally delayed general flow. The first one uses the measurement calculus formalism to rewrite the dependencies of an existing computation, whereas the second technique exploits the geometry of the resource state to find the optimal ordering of measurements. We prove that the aforementioned methods result in same depth computations when the input and output sizes are equal. Through showing this equivalence we reveal new properties of 1WQC computations and design a new algorithm for the above mentioned parallelisations.

Subjects/Keywords: 006.3; quantum computing

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APA (6^th Edition):

Pius, E. (2015). Parallel quantum computing : from theory to practice. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/15857

Chicago Manual of Style (16^th Edition):

Pius, Einar. “Parallel quantum computing : from theory to practice.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed November 20, 2019. http://hdl.handle.net/1842/15857.

MLA Handbook (7^th Edition):

Pius, Einar. “Parallel quantum computing : from theory to practice.” 2015. Web. 20 Nov 2019.

Vancouver:

Pius E. Parallel quantum computing : from theory to practice. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1842/15857.

Council of Science Editors:

Pius E. Parallel quantum computing : from theory to practice. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/15857

8. Morley-Short, Sam. Towards realistic architectures for linear optical quantum computing.

Degree: PhD, 2019, University of Bristol

URL: http://hdl.handle.net/1983/ecf3e9e6-3287-4dcd-871b-d879a8bf0bec

► With the end of Moore's Law within sight, quantum computers offer a tantalising paradigm shift in computational power. Currently, many quanta are competing to realise… (more)

▼ With the end of Moore's Law within sight, quantum computers offer a tantalising paradigm shift in computational power. Currently, many quanta are competing to realise such a revolutionary device, of which this thesis considers one in particular: linear optical quantum computation (LOQC). Over the past decade LOQC architectures have developed from "efficient" but unfeasible toy models to serious contenders. A significant step in previous works was the blueprint of an LOQC architecture that could be conceivably implemented with idealised optical components. However, in reality nature is not kind and devices not ideal. As such, we consider open questions addressing gaps between LOQC's theoretical architecture and experimental constraints. In doing so, a selection of numerical tools are also developed for the design, simulation and analyses of novel architectures. Specifically, we consider three problems. Firstly, can an infinite-sized quantum state be realised within a finite-sized device? Through development of a simple, generalised model, we find some small, finite device size at which the infinite state is faithfully reproduced. We also find that increasing device size above this confers no advantage, thereby identifying some necessary and sufficient minimum LOQC device size. Secondly, we consider the challenge of accommodating unheralded photon loss in an LOQC architecture, a problem for which no previous solution was known. By developing a novel protocol for optimal teleportation on stabilizer states, we show that unheralded loss may be tolerated, perhaps entirely, by adaptive measurement strategies. Finally, we consider the optimisation of LOQC architectures via local complementation. This work both sets hard limits on the states accessible by postselected linear optics circuits as well as develops novel tools for the analysis of higher-dimensional quantum states. We conclude with an example of how such works can be combined to optimise the LOQC architecture as well as provide improved device resource estimates.

Subjects/Keywords: quantum computing; linear optical quantum computing; photonics; quantum computing architectures

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APA (6^th Edition):

Morley-Short, S. (2019). Towards realistic architectures for linear optical quantum computing. (Doctoral Dissertation). University of Bristol. Retrieved from http://hdl.handle.net/1983/ecf3e9e6-3287-4dcd-871b-d879a8bf0bec

Chicago Manual of Style (16^th Edition):

Morley-Short, Sam. “Towards realistic architectures for linear optical quantum computing.” 2019. Doctoral Dissertation, University of Bristol. Accessed November 20, 2019. http://hdl.handle.net/1983/ecf3e9e6-3287-4dcd-871b-d879a8bf0bec.

MLA Handbook (7^th Edition):

Morley-Short, Sam. “Towards realistic architectures for linear optical quantum computing.” 2019. Web. 20 Nov 2019.

Vancouver:

Morley-Short S. Towards realistic architectures for linear optical quantum computing. [Internet] [Doctoral dissertation]. University of Bristol; 2019. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1983/ecf3e9e6-3287-4dcd-871b-d879a8bf0bec.

Council of Science Editors:

Morley-Short S. Towards realistic architectures for linear optical quantum computing. [Doctoral Dissertation]. University of Bristol; 2019. Available from: http://hdl.handle.net/1983/ecf3e9e6-3287-4dcd-871b-d879a8bf0bec

Wesleyan University

9. Kan, Angus. Quantum Computing: Temperature Scaling of Decoherence.

Degree: Physics, 2018, Wesleyan University

URL: https://wesscholar.wesleyan.edu/etd_mas_theses/193

► After years of effort by quantum scientists, decoherence due to thermal effects still remains a huge hindrance to the upscaling of quantum computers. This… (more)

Subjects/Keywords: Quantum; Quantum Computing; Quantum Information; Decoherence

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APA (6^th Edition):

Kan, A. (2018). Quantum Computing: Temperature Scaling of Decoherence. (Masters Thesis). Wesleyan University. Retrieved from https://wesscholar.wesleyan.edu/etd_mas_theses/193

Chicago Manual of Style (16^th Edition):

Kan, Angus. “Quantum Computing: Temperature Scaling of Decoherence.” 2018. Masters Thesis, Wesleyan University. Accessed November 20, 2019. https://wesscholar.wesleyan.edu/etd_mas_theses/193.

MLA Handbook (7^th Edition):

Kan, Angus. “Quantum Computing: Temperature Scaling of Decoherence.” 2018. Web. 20 Nov 2019.

Vancouver:

Kan A. Quantum Computing: Temperature Scaling of Decoherence. [Internet] [Masters thesis]. Wesleyan University; 2018. [cited 2019 Nov 20]. Available from: https://wesscholar.wesleyan.edu/etd_mas_theses/193.

Council of Science Editors:

Kan A. Quantum Computing: Temperature Scaling of Decoherence. [Masters Thesis]. Wesleyan University; 2018. Available from: https://wesscholar.wesleyan.edu/etd_mas_theses/193

University of Waterloo

10. 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)

Subjects/Keywords: Quantum physics; Quantum computing; Quantum control

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APA (6^th 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 (16^th Edition):

Layden, David. “Indirect Quantum Control: An Implementation-Independent Scheme.” 2016. Thesis, University of Waterloo. Accessed November 20, 2019. 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 (7^th Edition):

Layden, David. “Indirect Quantum Control: An Implementation-Independent Scheme.” 2016. Web. 20 Nov 2019.

Vancouver:

Layden D. Indirect Quantum Control: An Implementation-Independent Scheme. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2019 Nov 20]. 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

University of Waterloo

11. 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 gamma_2-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(n^3/2) and those that do have such a characterization can be solved strictly faster, with o(n^3/2) 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 (6^th 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 (16^th Edition):

Kothari, Robin. “Efficient algorithms in quantum query complexity.” 2014. Thesis, University of Waterloo. Accessed November 20, 2019. 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 (7^th Edition):

Kothari, Robin. “Efficient algorithms in quantum query complexity.” 2014. Web. 20 Nov 2019.

Vancouver:

Kothari R. Efficient algorithms in quantum query complexity. [Internet] [Thesis]. University of Waterloo; 2014. [cited 2019 Nov 20]. 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 New Mexico

12. 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)

Subjects/Keywords: physics; quantum; quantum computing; quantum memory

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APA (6^th 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 (16^th Edition):

Cesare, Christopher. “Topological Code Architectures for Quantum Computation.” 2014. Doctoral Dissertation, University of New Mexico. Accessed November 20, 2019. http://hdl.handle.net/1928/24543.

MLA Handbook (7^th Edition):

Cesare, Christopher. “Topological Code Architectures for Quantum Computation.” 2014. Web. 20 Nov 2019.

Vancouver:

Cesare C. Topological Code Architectures for Quantum Computation. [Internet] [Doctoral dissertation]. University of New Mexico; 2014. [cited 2019 Nov 20]. 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

13. 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)

Subjects/Keywords: Quantum Algorithm; Quantum Computing; Quantum Walks

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APA (6^th 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 (16^th Edition):

Schmitz, Albert Thomas. “Quantum Walks: Theory, Application, And Implementation.” 2016. Masters Thesis, University of North Dakota. Accessed November 20, 2019. https://commons.und.edu/theses/1959.

MLA Handbook (7^th Edition):

Schmitz, Albert Thomas. “Quantum Walks: Theory, Application, And Implementation.” 2016. Web. 20 Nov 2019.

Vancouver:

Schmitz AT. Quantum Walks: Theory, Application, And Implementation. [Internet] [Masters thesis]. University of North Dakota; 2016. [cited 2019 Nov 20]. 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

Australian National University

14. Nguyen, Thien. Topics in Quantum Computing Architecture .

Degree: 2018, Australian National University

URL: http://hdl.handle.net/1885/163717

► Quantum computing, which is considered the next revolution of computing technology, brings together theories of mathematics, physics, and computer science. Building a quantum computer thus… (more)

▼ Quantum computing, which is considered the next revolution of computing technology, brings together theories of mathematics, physics, and computer science. Building a quantum computer thus requires a synthesis of knowledge and skills from multiple disciplines. In this thesis, we take a step toward bridging and connecting the full "stack" of quantum computing technology which spans across theoretical foundations, hardware architecture, software and simulation. At the foundation level, we study one of the central problems of quantum computing, namely quantum error correction, from a control-engineering perspective. This approach not only complements the conventional coding-based interpretation but also provides a potential pathway to designing self-correcting quantum computers. First, we analyse the surface-code quantum error correction under a continuous feedback-based protocol. Second, we study the fundamental question of self-correcting quantum systems using the control method of reservoir engineering. Next, we study the scalability of a generic surface code quantum computer based on spin qubits such as quantum dots and donor atoms. Solid-state qubits (quantum dots and donor atoms), especially those that are Si-based, share similarities in device structures and manufacturing processes with advanced semiconductor CMOS industry. However, scaling up those quantum devices present immense challenges related to connectivity. By applying tools and methods from the semiconductor industry, we can concretely estimate the routing limitation of a planar connectivity scheme. Finally, as part of my PhD education at the Australian National University, I took part in an industry-based research internship to develop a high-performance quantum simulator. We provide the full description of the software architecture, implementation details, and benchmarking results of the simulator.

Subjects/Keywords: quantum computing; quantum control; quantum simulation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nguyen, T. (2018). Topics in Quantum Computing Architecture . (Thesis). Australian National University. Retrieved from http://hdl.handle.net/1885/163717

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nguyen, Thien. “Topics in Quantum Computing Architecture .” 2018. Thesis, Australian National University. Accessed November 20, 2019. http://hdl.handle.net/1885/163717.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nguyen, Thien. “Topics in Quantum Computing Architecture .” 2018. Web. 20 Nov 2019.

Vancouver:

Nguyen T. Topics in Quantum Computing Architecture . [Internet] [Thesis]. Australian National University; 2018. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1885/163717.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nguyen T. Topics in Quantum Computing Architecture . [Thesis]. Australian National University; 2018. Available from: http://hdl.handle.net/1885/163717

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Princeton University

15. 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)

Subjects/Keywords: quantum computing; quantum electrodynamics; quantum optics

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APA (6^th 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 (16^th Edition):

Liu, Yanbing. “Reservoir engineering in circuit quantum electrodynamics .” 2016. Doctoral Dissertation, Princeton University. Accessed November 20, 2019. http://arks.princeton.edu/ark:/88435/dsp01mw22v794j.

MLA Handbook (7^th Edition):

Liu, Yanbing. “Reservoir engineering in circuit quantum electrodynamics .” 2016. Web. 20 Nov 2019.

Vancouver:

Liu Y. Reservoir engineering in circuit quantum electrodynamics . [Internet] [Doctoral dissertation]. Princeton University; 2016. [cited 2019 Nov 20]. 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

University of Waterloo

16. Chamberland, Christopher. New methods in quantum error correction and fault-tolerant quantum computing.

Degree: 2018, University of Waterloo

URL: http://hdl.handle.net/10012/14049

► Quantum computers have the potential to solve several interesting problems in polynomial time for which no polynomial time classical algorithms have been found. However, one… (more)

▼ Quantum computers have the potential to solve several interesting problems in polynomial time for which no polynomial time classical algorithms have been found. However, one of the major challenges in building quantum devices is that quantum systems are very sensitive to noise arising from undesired interactions with the environment. Noise can lead to errors which can corrupt the results of the computation. Quantum error correction is one way to mitigate the effects of noise arising in quantum devices. With a plethora of quantum error correcting codes that can be used in various settings, one of the main challenges of quantum error correction is understanding how well various codes perform under more realistic noise models that can be observed in experiments. This thesis proposes a new decoding algorithm which can optimize threshold values of error correcting codes under different noise models. The algorithm can be applied to any Markovian noise model. Further, it is shown that for certain noise models, logical Clifford corrections can further improve a code's threshold value if the code obeys certain symmetries. Since gates and measurements cannot in general be performed with perfect precision, the operations required to perform quantum error correction can introduce more errors into the system thus negating the benefits of error correction. Fault-tolerant quantum computing is a way to perform quantum error correction with imperfect operations while retaining the ability to suppress errors as long as the noise is below a code's threshold. One of the main challenges in performing fault-tolerant error correction is the high resource requirements that are needed to obtain very low logical noise rates. With the use of flag qubits, this thesis develops new fault-tolerant error correction protocols that are applicable to arbitrary distance codes. Various code families are shown to satisfy the requirements of flag fault-tolerant error correction. We also provide circuits using a constant number of qubits for these codes. It is shown that the proposed flag fault-tolerant method uses fewer qubits than previous fault-tolerant error correction protocols. It is often the case that the noise afflicting a quantum device cannot be fully characterized. Further, even with some knowledge of the noise, it can be very challenging to use analytic decoding methods to improve the performance of a fault-tolerant scheme. This thesis presents decoding schemes using several state of the art machine learning techniques with a focus on fault-tolerant quantum error correction in regimes that are relevant to near term experiments. It is shown that even in low noise rate regimes and with no knowledge of the noise, noise can be further suppressed for small distance codes. Limitations of machine learning decoders as well as the classical resources required to perform active error correction are discussed. In many cases, gate times can be much shorter than typical measurement times of quantum states.…

Subjects/Keywords: Quantum error correction; Quantum computing; Fault-tolerant quantum computing; Quantum information

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APA (6^th Edition):

Chamberland, C. (2018). New methods in quantum error correction and fault-tolerant quantum computing. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/14049

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chamberland, Christopher. “New methods in quantum error correction and fault-tolerant quantum computing.” 2018. Thesis, University of Waterloo. Accessed November 20, 2019. http://hdl.handle.net/10012/14049.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chamberland, Christopher. “New methods in quantum error correction and fault-tolerant quantum computing.” 2018. Web. 20 Nov 2019.

Vancouver:

Chamberland C. New methods in quantum error correction and fault-tolerant quantum computing. [Internet] [Thesis]. University of Waterloo; 2018. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10012/14049.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chamberland C. New methods in quantum error correction and fault-tolerant quantum computing. [Thesis]. University of Waterloo; 2018. Available from: http://hdl.handle.net/10012/14049

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Harvard University

17. Tempel, David Gabriel. Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation.

Degree: PhD, Physics, 2012, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9396424

►

First-principles electronic structure theory explains properties of atoms, molecules and solids from underlying physical principles without input from empirical parameters. Time-dependent density functional theory (TDDFT)… (more)

▼

First-principles electronic structure theory explains properties of atoms, molecules and solids from underlying physical principles without input from empirical parameters. Time-dependent density functional theory (TDDFT) has emerged as arguably the most widely used first-principles method for describing the time-dependent quantum mechanics of many-electron systems. In this thesis, we will show how the fundamental principles of TDDFT can be extended and applied in two novel directions: The theory of open quantum systems (OQS) and quantum computation (QC). In the first part of this thesis, we prove theorems that establish the foundations of TDDFT for open quantum systems (OQS-TDDFT). OQS-TDDFT allows for a first principles description of non-equilibrium systems, in which the electronic degrees of freedom undergo relaxation and decoherence due to coupling with a thermal environment, such as a vibrational or photon bath. We then discuss properties of functionals in OQS-TDDFT and investigate how these differ from functionals in conventional TDDFT using an exactly solvable model system. Next, we formulate OQS-TDDFT in the linear-response regime, which gives access to environmentally broadened excitation spectra. Lastly, we present a hybrid approach in which TDDFT can be used to construct master equations from first-principles for describing energy transfer in condensed phase systems. In the second part of this thesis, we prove that the theorems of TDDFT can be extended to a class of qubit Hamiltonians that are universal for quantum computation. TDDFT applied to universal Hamiltonians implies that single-qubit expectation values can be used as the basic variables in quantum computation and information theory, rather than wavefunctions. This offers the possibility of simplifying computations by using the principles of TDDFT similar to how it is applied in electronic structure theory. Lastly, we discuss a related result; the computational complexity of TDDFT.

Physics

Advisors/Committee Members: Aspuru-Guzik, Alan (advisor).

Subjects/Keywords: open quantum systems; quantum computing; TDDFT; physics

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APA (6^th Edition):

Tempel, D. G. (2012). Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:9396424

Chicago Manual of Style (16^th Edition):

Tempel, David Gabriel. “Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation.” 2012. Doctoral Dissertation, Harvard University. Accessed November 20, 2019. http://nrs.harvard.edu/urn-3:HUL.InstRepos:9396424.

MLA Handbook (7^th Edition):

Tempel, David Gabriel. “Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation.” 2012. Web. 20 Nov 2019.

Vancouver:

Tempel DG. Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation. [Internet] [Doctoral dissertation]. Harvard University; 2012. [cited 2019 Nov 20]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9396424.

Council of Science Editors:

Tempel DG. Time-Dependent Density Functional Theory for Open Quantum Systems and Quantum Computation. [Doctoral Dissertation]. Harvard University; 2012. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9396424

Columbia University

18. Hadfield, Stuart Andrew. Quantum Algorithms for Scientific Computing and Approximate Optimization.

Degree: 2018, Columbia University

URL: https://doi.org/10.7916/D8X650C9

► Quantum computation appears to offer significant advantages over classical computation and this has generated a tremendous interest in the field. In this thesis we study… (more)

▼ Quantum computation appears to offer significant advantages over classical computation and this has generated a tremendous interest in the field. In this thesis we study the application of quantum computers to computational problems in science and engineering, and to combinatorial optimization problems. We outline the results below. Algorithms for scientific computing require modules, i.e., building blocks, implementing elementary numerical functions that have well-controlled numerical error, are uniformly scalable and reversible, and that can be implemented efficiently. We derive quantum algorithms and circuits for computing square roots, logarithms, and arbitrary fractional powers, and derive worst-case error and cost bounds. We describe a modular approach to quantum algorithm design as a first step towards numerical standards and mathematical libraries for quantum scientific computing. A fundamental but computationally hard problem in physics is to solve the time-independent Schrödinger equation. This is accomplished by computing the eigenvalues of the corresponding Hamiltonian operator. The eigenvalues describe the different energy levels of a system. The cost of classical deterministic algorithms computing these eigenvalues grows exponentially with the number of system degrees of freedom. The number of degrees of freedom is typically proportional to the number of particles in a physical system. We show an efficient quantum algorithm for approximating a constant number of low-order eigenvalues of a Hamiltonian using a perturbation approach. We apply this algorithm to a special case of the Schrödinger equation and show that our algorithm succeeds with high probability, and has cost that scales polynomially with the number of degrees of freedom and the reciprocal of the desired accuracy. This improves and extends earlier results on quantum algorithms for estimating the ground state energy. We consider the simulation of quantum mechanical systems on a quantum computer. We show a novel divide and conquer approach for Hamiltonian simulation. Using the Hamiltonian structure, we can obtain faster simulation algorithms. Considering a sum of Hamiltonians we split them into groups, simulate each group separately, and combine the partial results. Simulation is customized to take advantage of the properties of each group, and hence yield refined bounds to the overall simulation cost. We illustrate our results using the electronic structure problem of quantum chemistry, where we obtain significantly improved cost estimates under mild assumptions. We turn to combinatorial optimization problems. An important open question is whether quantum computers provide advantages for the approximation of classically hard combinatorial problems. A promising recently proposed approach of Farhi et al. is the Quantum Approximate Optimization Algorithm (QAOA). We study the application of QAOA to the Maximum Cut problem, and derive analytic performance bounds for the lowest circuit-depth realization, for both general and…

Subjects/Keywords: Computer science; Quantum theory; Quantum computing; Algorithms

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APA (6^th Edition):

Hadfield, S. A. (2018). Quantum Algorithms for Scientific Computing and Approximate Optimization. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/D8X650C9

Chicago Manual of Style (16^th Edition):

Hadfield, Stuart Andrew. “Quantum Algorithms for Scientific Computing and Approximate Optimization.” 2018. Doctoral Dissertation, Columbia University. Accessed November 20, 2019. https://doi.org/10.7916/D8X650C9.

MLA Handbook (7^th Edition):

Hadfield, Stuart Andrew. “Quantum Algorithms for Scientific Computing and Approximate Optimization.” 2018. Web. 20 Nov 2019.

Vancouver:

Hadfield SA. Quantum Algorithms for Scientific Computing and Approximate Optimization. [Internet] [Doctoral dissertation]. Columbia University; 2018. [cited 2019 Nov 20]. Available from: https://doi.org/10.7916/D8X650C9.

Council of Science Editors:

Hadfield SA. Quantum Algorithms for Scientific Computing and Approximate Optimization. [Doctoral Dissertation]. Columbia University; 2018. Available from: https://doi.org/10.7916/D8X650C9

Indiana University

19. Tai, Yu-Tsung. Discrete Quantum Theories and Computing .

Degree: 2019, Indiana University

URL: http://hdl.handle.net/2022/23178

► Most quantum computing models are based on the continuum of real numbers, while classical digital computers faithfully realize only discrete computational models. Analog computers appear… (more)

Subjects/Keywords: quantum computing; finite fields; quantum probability

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APA (6^th Edition):

Tai, Y. (2019). Discrete Quantum Theories and Computing . (Thesis). Indiana University. Retrieved from http://hdl.handle.net/2022/23178

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tai, Yu-Tsung. “Discrete Quantum Theories and Computing .” 2019. Thesis, Indiana University. Accessed November 20, 2019. http://hdl.handle.net/2022/23178.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tai, Yu-Tsung. “Discrete Quantum Theories and Computing .” 2019. Web. 20 Nov 2019.

Vancouver:

Tai Y. Discrete Quantum Theories and Computing . [Internet] [Thesis]. Indiana University; 2019. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/2022/23178.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tai Y. Discrete Quantum Theories and Computing . [Thesis]. Indiana University; 2019. Available from: http://hdl.handle.net/2022/23178

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

20. Hwang, Jason. Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing.

Degree: Electrical Engineering & Telecommunications, 2017, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/57223 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42863/SOURCE02?view=true

► A quantum computer utilizes the laws of quantum mechanics and performs logic operations on quantum two-level systems, known as quantum bits, or qubits. In this… (more)

▼ A quantum computer utilizes the laws of quantum mechanics and performs logic operations on quantum two-level systems, known as quantum bits, or qubits. In this PhD thesis, the qubit is defined by the spin states of a single electron confined in a silicon metal-oxide-semiconductor (MOS) quantum dot, a platform that is highly compatible with the fabrication technology currently employed in today's semiconductor industry. We have realized a MOS quantum dot qubit using an isotopically-purified silicon substrate, with an on-chip single-electron transistor (SET) for spin readout and a broadband microwave line for delivering electron spin resonance (ESR) control pulses. The qubit has a coherence time of 28 ms and a control-fidelity of 99.6%, which is above the threshold required for fault-tolerant quantum computing. In addition, a gate voltage can be used to Stark shift the qubit's resonance frequency over 3000 times the minimum ESR linewidth, hence opening up the prospect of independent qubit addressability in a large-scale system. Next, we demonstrated a two-qubit logic operation via the exchange coupling of two electron spins. By combining a switchable exchange interaction using electrical pulses with single qubit rotations, we realize controlled-NOT (CNOT) operations and measure clear anti-correlations in the two-spin probabilities of the CNOT gate by independently reading out both qubits. We then explore qubits composed of either one or three electrons, with the excess electron spin residing in the lower or upper conduction-band valley states, respectively. We observe an opposite g-factor dependence as a function of the applied dc electric field in the two type of qubits, and subsequently, we formulate a modified effective mass theory that shows direct correlations between the spin-orbit coupling parameters and the g-factors in the two valleys. Finally we investigate spin qubits defined in a double quantum dot which has a small g-factor difference with respect to their exchange interaction. This enables us to simultaneously drive transitions of two individual spins between the T- and T+ triplet states using an ESR frequency that is not directly resonating with any of the two spins in the system. Advisors/Committee Members: Dzurak, Andrew, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW.

Subjects/Keywords: Qubits; Quantum Computing; Quantum Dots; Silicon

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APA (6^th Edition):

Hwang, J. (2017). Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/57223 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42863/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Hwang, Jason. “Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing.” 2017. Doctoral Dissertation, University of New South Wales. Accessed November 20, 2019. http://handle.unsw.edu.au/1959.4/57223 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42863/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Hwang, Jason. “Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing.” 2017. Web. 20 Nov 2019.

Vancouver:

Hwang J. Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing. [Internet] [Doctoral dissertation]. University of New South Wales; 2017. [cited 2019 Nov 20]. Available from: http://handle.unsw.edu.au/1959.4/57223 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42863/SOURCE02?view=true.

Council of Science Editors:

Hwang J. Silicon MOS Quantum Dot Qubits for Spin-Based Quantum Computing. [Doctoral Dissertation]. University of New South Wales; 2017. Available from: http://handle.unsw.edu.au/1959.4/57223 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:42863/SOURCE02?view=true

Princeton University

21. Zajac, David. Single Electron Spin Qubits in Silicon Quantum Dots .

Degree: PhD, 2018, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01f4752k519

► Electron spins in quantum dots form ideal two-level systems for implementing quantum computation in the solid state. While spin states can have extremely long quantum… (more)

Subjects/Keywords: Quantum Computing; Quantum Dots; Spin Qubits

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zajac, D. (2018). Single Electron Spin Qubits in Silicon Quantum Dots . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01f4752k519

Chicago Manual of Style (16^th Edition):

Zajac, David. “Single Electron Spin Qubits in Silicon Quantum Dots .” 2018. Doctoral Dissertation, Princeton University. Accessed November 20, 2019. http://arks.princeton.edu/ark:/88435/dsp01f4752k519.

MLA Handbook (7^th Edition):

Zajac, David. “Single Electron Spin Qubits in Silicon Quantum Dots .” 2018. Web. 20 Nov 2019.

Vancouver:

Zajac D. Single Electron Spin Qubits in Silicon Quantum Dots . [Internet] [Doctoral dissertation]. Princeton University; 2018. [cited 2019 Nov 20]. Available from: http://arks.princeton.edu/ark:/88435/dsp01f4752k519.

Council of Science Editors:

Zajac D. Single Electron Spin Qubits in Silicon Quantum Dots . [Doctoral Dissertation]. Princeton University; 2018. Available from: http://arks.princeton.edu/ark:/88435/dsp01f4752k519

Georgia Tech

22. Schieber, Matthew Cole. Optimizing computational kernels in quantum chemistry.

Degree: MS, Computational Science and Engineering, 2018, Georgia Tech

URL: http://hdl.handle.net/1853/59949

► Density fitting is a rank reduction technique popularly used in quantum chemistry in order to reduce the computational cost of evaluating, transforming, and processing the… (more)

Subjects/Keywords: Quantum chemistry; Parallel computing; High performance computing

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APA (6^th Edition):

Schieber, M. C. (2018). Optimizing computational kernels in quantum chemistry. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59949

Chicago Manual of Style (16^th Edition):

Schieber, Matthew Cole. “Optimizing computational kernels in quantum chemistry.” 2018. Masters Thesis, Georgia Tech. Accessed November 20, 2019. http://hdl.handle.net/1853/59949.

MLA Handbook (7^th Edition):

Schieber, Matthew Cole. “Optimizing computational kernels in quantum chemistry.” 2018. Web. 20 Nov 2019.

Vancouver:

Schieber MC. Optimizing computational kernels in quantum chemistry. [Internet] [Masters thesis]. Georgia Tech; 2018. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1853/59949.

Council of Science Editors:

Schieber MC. Optimizing computational kernels in quantum chemistry. [Masters Thesis]. Georgia Tech; 2018. Available from: http://hdl.handle.net/1853/59949

23. Niskanen, Antti O. Control of Quantum Evolution and Josephson Junction Circuits.

Degree: 2004, VTT Technical Research Centre of Finland

URL: http://lib.tkk.fi/Diss/2004/isbn9513864219/

►

Ever since Peter Shor's ground-breaking discovery in 1994 of an algorithm capable of factoring large integers on a quantum-mechanical computer exponentially faster than using any… (more)

▼

Ever since Peter Shor's ground-breaking discovery in 1994 of an algorithm capable of factoring large integers on a quantum-mechanical computer exponentially faster than using any known classical method, research on quantum computing has boomed. Quantum information – a unique mixture of computer science, physics and mathematics – has developed into a new branch of information theory. On the experimental side, physicists from many different disciplines including atomic, solid-state and low-temperature physics, as well as optics, are striving today towards a practical quantum computer. All the candidate quantum bit (qubit) technologies have one thing in common: They rely on the controlled time-evolution of a closed quantum system, a seemingly paradoxical task. In this Thesis the temporal control of quantum systems is studied. The topics included can be divided into two according to the type of temporal evolution; geometrical or dynamical. Geometrical realization-independent methods for quantum computing are studied first. Then the study is extended into dynamical quantum computing and the so-called Josephson charge-qubit register is considered as a test bench. Finally, a spin-off application of the geometrical evolution of a Josephson junction system is studied, i.e. Cooper pair pumping. A novel Cooper pair pump, the Cooper pair "sluice", is introduced. The work on quantum computing reported in this Thesis is theoretical while the Cooper pair "sluice" is studied both theoretically and experimentally. Numerical simulations, both sequential and parallel, are used extensively throughout the Thesis. The experiments were carried out under cryogenic mK conditions and the sample fabrication was done using e-beam nanolithography. Because the execution time of a quantum algorithm is always limited by the inevitable process of decoherence, it is important to utilize any measure available for accelerating quantum computations. It is found that practical quantum algorithms could greatly benefit from classical computer-aided optimization. Moreover, it is found that even a modest demonstrator of a full quantum algorithm using Josephson charge qubits is just barely realizable within present-day coherence times. However, the experimental part of this Thesis shows clear evidence of the functioning of the "sluice". While the worldwide effort of improving the coherence properties of qubits is underway, the "sluice" could well find practical use, e.g., in metrology in the foreseeable future.

VTT publications, ISSN 1455-0849; 552

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, VTT Information Technology.

Subjects/Keywords: quantum systems; quantum mechanics; quantum computing; quantum algorithms; Cooper pair pumping

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APA (6^th Edition):

Niskanen, A. O. (2004). Control of Quantum Evolution and Josephson Junction Circuits. (Thesis). VTT Technical Research Centre of Finland. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9513864219/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Niskanen, Antti O. “Control of Quantum Evolution and Josephson Junction Circuits.” 2004. Thesis, VTT Technical Research Centre of Finland. Accessed November 20, 2019. http://lib.tkk.fi/Diss/2004/isbn9513864219/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Niskanen, Antti O. “Control of Quantum Evolution and Josephson Junction Circuits.” 2004. Web. 20 Nov 2019.

Vancouver:

Niskanen AO. Control of Quantum Evolution and Josephson Junction Circuits. [Internet] [Thesis]. VTT Technical Research Centre of Finland; 2004. [cited 2019 Nov 20]. Available from: http://lib.tkk.fi/Diss/2004/isbn9513864219/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Niskanen AO. Control of Quantum Evolution and Josephson Junction Circuits. [Thesis]. VTT Technical Research Centre of Finland; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9513864219/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Boston University

24. Fitzpatrick, Casey Alan. High-dimensional quantum information processing with linear optics.

Degree: PhD, Electrical & Computer Engineering, 2017, Boston University

URL: http://hdl.handle.net/2144/23564

► Quantum information processing (QIP) is an interdisciplinary field concerned with the development of computers and information processing systems that utilize quantum mechanical properties of nature… (more)

▼ Quantum information processing (QIP) is an interdisciplinary field concerned with the development of computers and information processing systems that utilize quantum mechanical properties of nature to carry out their function. QIP systems have become vastly more practical since the turn of the century. Today, QIP applications span imaging, cryptographic security, computation, and simulation (quantum systems that mimic other quantum systems). Many important strategies improve quantum versions of classical information system hardware, such as single photon detectors and quantum repeaters. Another more abstract strategy engineers high-dimensional quantum state spaces, so that each successful event carries more information than traditional two-level systems allow. Photonic states in particular bring the added advantages of weak environmental coupling and data transmission near the speed of light, allowing for simpler control and lower system design complexity. In this dissertation, numerous novel, scalable designs for practical high-dimensional linear-optical QIP systems are presented. First, a correlated photon imaging scheme using orbital angular momentum (OAM) states to detect rotational symmetries in objects using measurements, as well as building images out of those interactions is reported. Then, a statistical detection method using chains of OAM superpositions distributed according to the Fibonacci sequence is established and expanded upon. It is shown that the approach gives rise to schemes for sorting, detecting, and generating the recursively defined high-dimensional states on which some quantum cryptographic protocols depend. Finally, an ongoing study based on a generalization of the standard optical multiport for applications in quantum computation and simulation is reported upon. The architecture allows photons to reverse momentum inside the device. This in turn enables realistic implementation of controllable linear-optical scattering vertices for carrying out quantum walks on arbitrary graph structures, a powerful tool for any quantum computer. It is shown that the novel architecture provides new, efficient capabilities for the optical quantum simulation of Hamiltonians and topologically protected states. Further, these simulations use exponentially fewer resources than feedforward techniques, scale linearly to higher-dimensional systems, and use only linear optics, thus offering a concrete experimentally achievable implementation of graphical models of discrete-time quantum systems.

Subjects/Keywords: Quantum physics; Optics; Photonics; Quantum computing; Quantum information processing; Quantum optics

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APA (6^th Edition):

Fitzpatrick, C. A. (2017). High-dimensional quantum information processing with linear optics. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/23564

Chicago Manual of Style (16^th Edition):

Fitzpatrick, Casey Alan. “High-dimensional quantum information processing with linear optics.” 2017. Doctoral Dissertation, Boston University. Accessed November 20, 2019. http://hdl.handle.net/2144/23564.

MLA Handbook (7^th Edition):

Fitzpatrick, Casey Alan. “High-dimensional quantum information processing with linear optics.” 2017. Web. 20 Nov 2019.

Vancouver:

Fitzpatrick CA. High-dimensional quantum information processing with linear optics. [Internet] [Doctoral dissertation]. Boston University; 2017. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/2144/23564.

Council of Science Editors:

Fitzpatrick CA. High-dimensional quantum information processing with linear optics. [Doctoral Dissertation]. Boston University; 2017. Available from: http://hdl.handle.net/2144/23564

University of California – San Diego

25. Sherkat-Massoom, Hooman. Quantum Algorithms for Searching Manifolds.

Degree: Mathematics, 2018, University of California – San Diego

URL: http://www.escholarship.org/uc/item/4934z45v

► Quantum computing is a system of computation that exploits the quantum-mechanical nature of reality at nano-scales in order to perform certain operations in a way… (more)

Subjects/Keywords: Mathematics; Quantum physics; Quantum algorithms; Quantum computing; Quantum information

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APA (6^th Edition):

Sherkat-Massoom, H. (2018). Quantum Algorithms for Searching Manifolds. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/4934z45v

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sherkat-Massoom, Hooman. “Quantum Algorithms for Searching Manifolds.” 2018. Thesis, University of California – San Diego. Accessed November 20, 2019. http://www.escholarship.org/uc/item/4934z45v.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sherkat-Massoom, Hooman. “Quantum Algorithms for Searching Manifolds.” 2018. Web. 20 Nov 2019.

Vancouver:

Sherkat-Massoom H. Quantum Algorithms for Searching Manifolds. [Internet] [Thesis]. University of California – San Diego; 2018. [cited 2019 Nov 20]. Available from: http://www.escholarship.org/uc/item/4934z45v.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sherkat-Massoom H. Quantum Algorithms for Searching Manifolds. [Thesis]. University of California – San Diego; 2018. Available from: http://www.escholarship.org/uc/item/4934z45v

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

26. Fisher, Kent. Photons & Phonons: A room-temperature diamond quantum memory.

Degree: 2016, University of Waterloo

URL: http://hdl.handle.net/10012/10663

► This thesis presents demonstrations of the storage and manipulation of single photons in a room-temperature diamond quantum memory using a Raman memory protocol. We report… (more)

▼ This thesis presents demonstrations of the storage and manipulation of single photons in a room-temperature diamond quantum memory using a Raman memory protocol. We report on results from four experiments. In the first we demonstrate single photon storage and, upon retrieval, verify the quantum nature of the light with a Hanbury Brown Twiss measurement of g^(2)(0) = 0.65±0.07. A measurement of g^(2)(0) < 1 is indicative of quantum light. This is the first demonstration of single photon storage where the bandwidth of the stored light is greater than 1 THz. The diamond memory stores light for over 13 times the duration of the input wavepacket. In the second experiment, we report the storage and retrieval of polarization-encoded qubits and demonstrate qubit storage above a classical bound. We also verify that entanglement between the input photon and an auxiliary persists through storage and retrieval. We then turn to additional uses of a Raman quantum memory. We demonstrate that a photon stored in the diamond memory can, upon retrieval, have its frequency and bandwidth converted. We report frequency conversion over a range of 4.2 times the bandwidth of the input photon (4.1 nm, 2.3 THz), and bandwidth modulation between 0.5 to 1.9 times the bandwidth of the input. We verify that the output light from storage and spectral manipulation is still non-classical in nature. Finally, we demonstrate both single- and two-photon quantum interference mediated by the diamond memory, where the memory acts as a beamsplitter between photon and optical phonon modes in the diamond lattice. In a first experiment, a single photon is split into two time-bins. The first time-bin is stored in the memory, then recalled and made to interfere with the second time-bin producing fringes. In a second experiment, a photon from a weak coherent state is stored in the memory and, upon retrieval, undergoes Hong- Ou-Mandel interference with a second photon. We measure Hong-Ou-Mandel interference with a visibility of 59% giving a signature of non-classical interference (> 50%). This collection of experiments establishes the diamond memory as a prime candidate for certain quantum communication and processing applications. These results demonstrate the potential for the diamond memory to be an integrated platform for photon storage, spectral conversion, and information processing.

Subjects/Keywords: Quantum optics; Quantum information; Quantum memory; Quantum computing

11 more images…

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APA (6^th Edition):

Fisher, K. (2016). Photons & Phonons: A room-temperature diamond quantum memory. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/10663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fisher, Kent. “Photons & Phonons: A room-temperature diamond quantum memory.” 2016. Thesis, University of Waterloo. Accessed November 20, 2019. http://hdl.handle.net/10012/10663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fisher, Kent. “Photons & Phonons: A room-temperature diamond quantum memory.” 2016. Web. 20 Nov 2019.

Vancouver:

Fisher K. Photons & Phonons: A room-temperature diamond quantum memory. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10012/10663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fisher K. Photons & Phonons: A room-temperature diamond quantum memory. [Thesis]. University of Waterloo; 2016. Available from: http://hdl.handle.net/10012/10663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

27. Marcos Villagra. On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ.

Degree: Nara Institute of Science and Technology / 奈良先端科学技術大学院大学

URL: http://hdl.handle.net/10061/8810

Subjects/Keywords: quantum computing

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APA (6^th Edition):

Villagra, M. (n.d.). On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ. (Thesis). Nara Institute of Science and Technology / 奈良先端科学技術大学院大学. Retrieved from http://hdl.handle.net/10061/8810

Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Villagra, Marcos. “On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ.” Thesis, Nara Institute of Science and Technology / 奈良先端科学技術大学院大学. Accessed November 20, 2019. http://hdl.handle.net/10061/8810.

Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Villagra, Marcos. “On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ.” Web. 20 Nov 2019.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Villagra M. On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ. [Internet] [Thesis]. Nara Institute of Science and Technology / 奈良先端科学技術大学院大学; [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10061/8810.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.

Council of Science Editors:

Villagra M. On the Power and Limitations of Quantum Computing Models : Quantum Walks and Communication Complexity : 量子計算モデルの能力と限界 : 量子ウォークと通信計算量; リョウシケイサンモデルノノウリョクトゲンカイ : リョウシウォークトツウシンケイサンリョウ. [Thesis]. Nara Institute of Science and Technology / 奈良先端科学技術大学院大学; Available from: http://hdl.handle.net/10061/8810

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.

University of Edinburgh

28. Kapourniotis, Theodoros. Efficient verification of universal and intermediate quantum computing.

Degree: PhD, 2016, University of Edinburgh

URL: http://hdl.handle.net/1842/25492

► The promise of scalable quantum technology appears more realistic, after recent advances in both theory and experiment. Assuming a quantum computer is developed, the task… (more)

▼ The promise of scalable quantum technology appears more realistic, after recent advances in both theory and experiment. Assuming a quantum computer is developed, the task of verifying the correctness of its outcome becomes crucial. Unfortunately, for a system that involves many particles, predicting its evolution via classical simulation becomes intractable. Moreover, verification of the outcome by computational methods, i.e. involving a classical witness, is believed inefficient for the hardest problems solvable by a quantum computer. A feasible alternative to verify quantum computation is via cryptographic methods, where an untrusted prover has to convince a weak verifier for the correctness of his outcome. This is the approach we take in this thesis. In the most standard configuration the prover is capable of computing all polynomial-time quantum circuits and the verifier is restricted to classical with very modest quantum power. The goal of existing verification protocols is to reduce the quantum requirements for the verifier - ideally making it purely classical - and reduce the communication complexity. In Part II we propose a composition of two existing verification protocols [Fitzsimons and Kashefi, 2012], [Aharonov et al., 2010] that achieves quadratic improvement in communication complexity, while keeping the quantum requirements for the verifier modest. Along this result, several new techniques are proposed, including the generalization of [Fitzsimons and Kashefi, 2012] to prime dimensions. In Part III we discuss the idea of model-specific quantum verification, where the prover is restricted to intermediate quantum power, i.e. between full-fledged quantum and purely classical, thus more feasible experimentally. As a proof of principle we propose a verification protocol for the One-Pure-Qubit computer [Knill and Laflamme, 1998], which tolerates noise and is capable of computing hard problems such as large matrix trace estimation. The verification protocol is an adaptation of [Fitzsimons and Kashefi, 2012] running on Measurement-Based Quantum Computing with newly proved properties of the underlying resources. Connections of quantum verification to other security primitives are considered in Part IV. Authenticated quantum communication has been already proved to relate to quantum verification. We expand this by proposing a quantum authentication protocol derived from [Fitzsimons and Kashefi, 2012] and discuss implications to verification with purely classical verifier. Connections between quantum security primitives, namely blindness - prover does not learn the computation -, and classical security are considered in Part V. We introduce a protocol where a client with restricted classical resources computes blindly a universal classical gate with the help of an untrusted server, by adding modest quantum capabilities to both client and server. This example of quantum-enhanced classical security we prove to be a task classically impossible.

Subjects/Keywords: 006.3; quantum computing; verification

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kapourniotis, T. (2016). Efficient verification of universal and intermediate quantum computing. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/25492

Chicago Manual of Style (16^th Edition):

Kapourniotis, Theodoros. “Efficient verification of universal and intermediate quantum computing.” 2016. Doctoral Dissertation, University of Edinburgh. Accessed November 20, 2019. http://hdl.handle.net/1842/25492.

MLA Handbook (7^th Edition):

Kapourniotis, Theodoros. “Efficient verification of universal and intermediate quantum computing.” 2016. Web. 20 Nov 2019.

Vancouver:

Kapourniotis T. Efficient verification of universal and intermediate quantum computing. [Internet] [Doctoral dissertation]. University of Edinburgh; 2016. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/1842/25492.

Council of Science Editors:

Kapourniotis T. Efficient verification of universal and intermediate quantum computing. [Doctoral Dissertation]. University of Edinburgh; 2016. Available from: http://hdl.handle.net/1842/25492

University of Waterloo

29. Gharibi, Mirmojtaba. The non-injective hidden shift problem.

Degree: 2012, University of Waterloo

URL: http://hdl.handle.net/10012/6478

► In this work, we mostly concentrate on the hidden shift problem for non-injective functions. It is worthwhile to know that the query complexity of the… (more)

▼ In this work, we mostly concentrate on the hidden shift problem for non-injective functions. It is worthwhile to know that the query complexity of the non-injective hidden shift problem is exponential in the worst case by the well known bounds on the unstructured search problem. Hence, we can make this problem more tractable by imposing additional constraints on the problem. Perhaps the first constraint that comes to mind is to address the average case problem. In this work, we show that the average case non-injective hidden shift problem can be reduced to the injective hidden shift problem by giving one such reduction. The reduction is based on a tool we developed called injectivization. The result is strong in the sense that the underlying group can be any finite group and that the non-injective functions for which we have defined the hidden shift problem can have range in an arbitrary finite set. Using this tool, we simplify the main result of a recent paper by about the hidden shift problem for Boolean-valued functions by reducing that problem to Simon's problem. They also posed an open question which is subject to personal interpretation. We answer the seemingly most general interpretation of the question. However, we use our own techniques in doing so (the authors ask if their techniques can be used for addressing that problem). Another constraint that one can consider is to have a promise on the structure of the functions. In this work we consider the hidden shift problem for c-almost generalized bent functions. A class of functions which we defined that includes the generalized bent functions. Then we turn our attention toward the generalized hidden shift problem which is easier than injective hidden shift problem and hence more tractable. We state some of our observations about this problem. Finally we show that the average classical query complexity of the non-injective hidden shift problem over groups of form (Z/mZ)^n when m is a constant is exponential, which also immediately implies that the classical average query complexity of the non-injective hidden shift problem is exponential. We also show that the worst-case classical query complexity of the generalized injective hidden shift problem over the same group is high, which implies that the classical query complexity of the hidden shift problem is high.

Subjects/Keywords: Quantum Computing; Hidden Shift Problem

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gharibi, M. (2012). The non-injective hidden shift problem. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/6478

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gharibi, Mirmojtaba. “The non-injective hidden shift problem.” 2012. Thesis, University of Waterloo. Accessed November 20, 2019. http://hdl.handle.net/10012/6478.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gharibi, Mirmojtaba. “The non-injective hidden shift problem.” 2012. Web. 20 Nov 2019.

Vancouver:

Gharibi M. The non-injective hidden shift problem. [Internet] [Thesis]. University of Waterloo; 2012. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10012/6478.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gharibi M. The non-injective hidden shift problem. [Thesis]. University of Waterloo; 2012. Available from: http://hdl.handle.net/10012/6478

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

30. Buech, Holger. Readout and addressability of Si:P qubits with the prospect of scalability.

Degree: ARC Centre of Excellence for Quantum Computer Technology, 2014, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/53836 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12549/SOURCE02?view=true

► In this thesis we present single-shot spin readout of precision placed phosphorus donors in silicon. The spin states of an electron bound to phosphorus donors… (more)

▼ In this thesis we present single-shot spin readout of precision placed phosphorus donors in silicon. The spin states of an electron bound to phosphorus donors in silicon make promising building blocks for the realisation of a solid state quantum computer due to their remarkably long coherence and relaxation times. Recent progress in scanning tunnelling microscope (STM) lithography has made it possible to place these donors with atomic accuracy, opening the way to individual qubit control and hence scalability.We present spin readout from two different STM-patterned devices where the electron spin qubit is hosted by either a cluster of about four phosphorus donors or a single phosphorus donor and tunnel-coupled to an atomically planar single electron transistor (SET). We demonstrate high fidelity (approx. 90%) single shot spin readout of the cluster qubit via spin-to-charge conversion and show long spin life times of T1 = 1.3 s (B=1.5 T) despite the multi-donor, multi-electron character of the spin qubit.For the single P donor we extrapolate a slightly larger T1 of approx. 6 s at B=1.5 T, consistent with previous measurements of single donor spin life times. Using atomistic tight-binding calculations, we confirm the dependency of the relaxation rate on both donor and electron numbers, where we show that multi-donor single-electron systems provide the highest T1. We also demonstrate the concept of using the single donor as a spectrometer to analyse the energy level structure of the SET island.Finally, the successful spin readout of the cluster qubit with long measured T1 provides an opportunity to use cluster qubits in conjunction with single donor qubits to achieve qubit addressability by a global microwave field with very low error rates. We show by atomistic tight binding modelling, that the electron spin resonance (ESR) frequency of a double donor qubit can be separated by up to 350 MHz from the ESR frequency of a single donor qubit due to the difference in the hyperfine coupling, allowing qubit rotations with error rates as low as approx. 10^(-5). Together, these results advance STM device fabrication technology towards the realisation of scalable donor based qubit architectures in silicon. Advisors/Committee Members: Simmons, Michelle, ARC Centre of Excellence for Quantum Computer Technology, Faculty of Science, UNSW.

Subjects/Keywords: Spin readout; STM; Quantum computing

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APA (6^th Edition):

Buech, H. (2014). Readout and addressability of Si:P qubits with the prospect of scalability. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/53836 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12549/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Buech, Holger. “Readout and addressability of Si:P qubits with the prospect of scalability.” 2014. Doctoral Dissertation, University of New South Wales. Accessed November 20, 2019. http://handle.unsw.edu.au/1959.4/53836 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12549/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Buech, Holger. “Readout and addressability of Si:P qubits with the prospect of scalability.” 2014. Web. 20 Nov 2019.

Vancouver:

Buech H. Readout and addressability of Si:P qubits with the prospect of scalability. [Internet] [Doctoral dissertation]. University of New South Wales; 2014. [cited 2019 Nov 20]. Available from: http://handle.unsw.edu.au/1959.4/53836 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12549/SOURCE02?view=true.

Council of Science Editors:

Buech H. Readout and addressability of Si:P qubits with the prospect of scalability. [Doctoral Dissertation]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/53836 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12549/SOURCE02?view=true

Open Access Theses and Dissertations