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Virginia Commonwealth University
1.
Grover, Cam J.
Nature of Bonding in Bimetallic or Ligated Aluminum Clusters.
Degree: MS, Physics and Applied Physics, 2017, Virginia Commonwealth University
URL: https://doi.org/10.25772/SGG9-JT82 
;
https://scholarscompass.vcu.edu/etd/4828
► In this study, Amsterdam Density Functional software is used to model bimetallic and ligated aluminum clusters. The stability of the bimetallic clusters is well…
(more)
▼ In this study, Amsterdam Density Functional software is used to model bimetallic and ligated aluminum clusters. The stability of the bimetallic clusters is well described by the Jellium model, and the nature of bonding between dopants and aluminum in the bimetallic clusters is analyzed using different criteria. We find that sodium tends to bind ionically, while the bonding of magnesium is not so obvious. We also determine that examining the Mulliken population is the most useful parameter in differentiating bonding character. Calculations on ligated aluminum clusters reveal it behaves fundamentally different than the bimetallic clusters studied in the first part. The ligated clusters contained a high HOMO-LUMO gap regardless of size and the aluminum showed a high 3p Mulliken population. These results show ligated aluminum clusters behave according to Wade-Mingos counting rules.
Advisors/Committee Members: Shiv Khanna, Marilyn Bishop, Alenka Luzar, Arthur Reber.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Grover, C. J. (2017). Nature of Bonding in Bimetallic or Ligated Aluminum Clusters. (Thesis). Virginia Commonwealth University. Retrieved from https://doi.org/10.25772/SGG9-JT82 ; https://scholarscompass.vcu.edu/etd/4828
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):
Grover, Cam J. “Nature of Bonding in Bimetallic or Ligated Aluminum Clusters.” 2017. Thesis, Virginia Commonwealth University. Accessed March 02, 2021.
https://doi.org/10.25772/SGG9-JT82 ; https://scholarscompass.vcu.edu/etd/4828.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Grover, Cam J. “Nature of Bonding in Bimetallic or Ligated Aluminum Clusters.” 2017. Web. 02 Mar 2021.
Vancouver:
Grover CJ. Nature of Bonding in Bimetallic or Ligated Aluminum Clusters. [Internet] [Thesis]. Virginia Commonwealth University; 2017. [cited 2021 Mar 02].
Available from: https://doi.org/10.25772/SGG9-JT82 ; https://scholarscompass.vcu.edu/etd/4828.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Grover CJ. Nature of Bonding in Bimetallic or Ligated Aluminum Clusters. [Thesis]. Virginia Commonwealth University; 2017. Available from: https://doi.org/10.25772/SGG9-JT82 ; https://scholarscompass.vcu.edu/etd/4828
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
College of William and Mary
2.
Romanov, Gleb Vladimirovich.
Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms.
Degree: PhD, Physics, 2017, College of William and Mary
URL: https://scholarworks.wm.edu/etd/1516639561
► In the last few decades, coherent light-atom interactions have opened unprecedented possibilities for the coherent control of atomic and optical quantum systems, paved the way…
(more)
▼ In the last few decades, coherent light-atom interactions have opened unprecedented possibilities for the coherent control of atomic and optical quantum systems, paved the way for the practical realization of quantum information technologies, and allowed for the creation of novel quantum-enhanced sensors. This dissertation investigates the interaction of multiple near-resonant optical fields with hot rubidium atoms under the conditions of electromagnetically induced transparency. The main goal of the presented research is to address some fundamental challenges in using such systems for practical applications. The EIT effect relies on the strong coupling of an optical probe field and a collective long-lived ensemble of atomic spins by the means of a strong classical optical control field in a Lambda configuration. While optically-thick atomic vapor is necessary to achieve such a strong coupling regime, the increasing optical depth of the atomic ensemble also leads to the effective enhancement of other nonlinear light-atom interactions, such as the four-wave mixing effect. Here we discuss the possibility to control four-wave mixing in a three-level system without deteriorating the coherent properties of EIT by introducing an additional absorber resonant exclusively with the Stokes field. The exclusive detection of a weak probe field in the presence of a strong control field is a challenging experimental task, especially at the few-photon level. Many experiments employ polarization and/or frequency filtering to compete the task. We present an alternative filtering technique based on optical vortices for cases when the traditional methods are not sufficient or restrict the experimental arrangements. Finally, we demonstrate the possibility to manipulate the group velocity of a pulsed squeezed vacuum field by using the optical dispersion modification via Zeeman spin coherence in rubidium atoms. By changing the interaction condition, we demonstrate the switch between the ``slow'' and (for the first time) ``fast'' light regime. We also show that increased optical depth simultaneously leads to the enhancement of pulse advancement and the deterioration of squeezing fidelity in the output pulses.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Romanov, G. V. (2017). Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms. (Doctoral Dissertation). College of William and Mary. Retrieved from https://scholarworks.wm.edu/etd/1516639561
Chicago Manual of Style (16th Edition):
Romanov, Gleb Vladimirovich. “Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms.” 2017. Doctoral Dissertation, College of William and Mary. Accessed March 02, 2021.
https://scholarworks.wm.edu/etd/1516639561.
MLA Handbook (7th Edition):
Romanov, Gleb Vladimirovich. “Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms.” 2017. Web. 02 Mar 2021.
Vancouver:
Romanov GV. Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms. [Internet] [Doctoral dissertation]. College of William and Mary; 2017. [cited 2021 Mar 02].
Available from: https://scholarworks.wm.edu/etd/1516639561.
Council of Science Editors:
Romanov GV. Optical Control of Multi-Photon Coherent Interactions in Rubidium Atoms. [Doctoral Dissertation]. College of William and Mary; 2017. Available from: https://scholarworks.wm.edu/etd/1516639561
College of William and Mary
3.
Gambhir, Arjun Singh.
Disconnected Diagrams in Lattice Qcd.
Degree: PhD, Physics, 2017, College of William and Mary
URL: https://scholarworks.wm.edu/etd/1516639772
► In this work, we present state-of-the-art numerical methods and their applications for computing a particular class of observables using lattice quantum chromodynamics (Lattice QCD), a…
(more)
▼ In this work, we present state-of-the-art numerical methods and their applications for computing a particular class of observables using lattice quantum chromodynamics (Lattice QCD), a discretized version of the fundamental theory of quarks and gluons. These observables require calculating so called "disconnected diagrams" and are important for understanding many aspects of hadron structure, such as the strange content of the proton. We begin by introducing the reader to the key concepts of Lattice QCD and rigorously define the meaning of disconnected diagrams through an example of the Wick contractions of the nucleon. Subsequently, the calculation of observables requiring disconnected diagrams is posed as the computationally challenging problem of finding the trace of the inverse of an incredibly large, sparse matrix. This is followed by a brief primer of numerical sparse matrix techniques that overviews broadly used methods in Lattice QCD and builds the background for the novel algorithm presented in this work. We then introduce singular value deflation as a method to improve convergence of trace estimation and analyze its effects on matrices from a variety of fields, including chemical transport modeling, magnetohydrodynamics, and QCD. Finally, we apply this method to compute observables such as the strange axial charge of the proton and strange sigma terms in light nuclei. The work in this thesis is innovative for four reasons. First, we analyze the effects of deflation with a model that makes qualitative predictions about its effectiveness, taking only the singular value spectrum as input, and compare deflated variance with different types of trace estimator noise. Second, the synergy between probing methods and deflation is investigated both experimentally and theoretically. Third, we use the synergistic combination of deflation and a graph coloring algorithm known as hierarchical probing to conduct a lattice calculation of light disconnected matrix elements of the nucleon at two different values of the lattice spacing. Finally, we employ these algorithms to do a high-precision study of strange sigma terms in light nuclei; to our knowledge this is the first calculation of its kind from Lattice QCD.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Gambhir, A. S. (2017). Disconnected Diagrams in Lattice Qcd. (Doctoral Dissertation). College of William and Mary. Retrieved from https://scholarworks.wm.edu/etd/1516639772
Chicago Manual of Style (16th Edition):
Gambhir, Arjun Singh. “Disconnected Diagrams in Lattice Qcd.” 2017. Doctoral Dissertation, College of William and Mary. Accessed March 02, 2021.
https://scholarworks.wm.edu/etd/1516639772.
MLA Handbook (7th Edition):
Gambhir, Arjun Singh. “Disconnected Diagrams in Lattice Qcd.” 2017. Web. 02 Mar 2021.
Vancouver:
Gambhir AS. Disconnected Diagrams in Lattice Qcd. [Internet] [Doctoral dissertation]. College of William and Mary; 2017. [cited 2021 Mar 02].
Available from: https://scholarworks.wm.edu/etd/1516639772.
Council of Science Editors:
Gambhir AS. Disconnected Diagrams in Lattice Qcd. [Doctoral Dissertation]. College of William and Mary; 2017. Available from: https://scholarworks.wm.edu/etd/1516639772
University of Colorado
4.
Stuhl, Benjamin Kojm.
Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping.
Degree: PhD, Physics, 2012, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/81
► While cold molecule experiments are rapidly moving towards their promised benefits of precision spectroscopy, controllable chemistry, and novel condensed phases, heretofore the field has…
(more)
▼ While cold molecule experiments are rapidly moving towards their promised benefits of precision spectroscopy, controllable chemistry, and novel condensed phases, heretofore the field has been greatly limited by a lack of methods to cool and compress chemically diverse species to temperatures below ten millikelvin. While in atomic
physics these needs are fulfilled by laser cooling, magneto-
optical trapping, and evaporative cooling, until now none of these techniques have been applicable to molecules. In this thesis, two major breakthroughs are reported. The first is the observation of evaporative cooling in magnetically trapped hydroxyl (OH) radicals, which potentially opens a path all the way to Bose-Einstein condensation of dipolar radicals, as well as allowing cold- and ultracold-chemistry studies of fundamental reaction mechanisms. Through the combination of an extremely high gradient magnetic quadrupole trap and the use of the OH Λ-doublet transition to enable highly selective forced evaporation, cooling by an order of magnitude in temperature was achieved and yielded a final temperature no higher than 5mK. The second breakthrough is the successful application of laser cooling and magneto-
optical trapping to molecules. Motivated by a proposal in this thesis, laser cooling of molecules is now known to be technically feasible in a select but substantial pool of diatomic molecules. The demonstration of not only Doppler cooling but also two-dimensional magneto-
optical trapping in yttrium (II) oxide, YO, is expected to enable rapid growth in the availability of ultracold molecules – just as the invention of the atomic magneto-
optical trap stimulated atomic
physics twenty-five years ago.
Advisors/Committee Members: Jun Ye, Eric Cornell, John L. Bohn, Deborah Jin, Carl Lineberger.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Stuhl, B. K. (2012). Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/81
Chicago Manual of Style (16th Edition):
Stuhl, Benjamin Kojm. “Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping.” 2012. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/81.
MLA Handbook (7th Edition):
Stuhl, Benjamin Kojm. “Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping.” 2012. Web. 02 Mar 2021.
Vancouver:
Stuhl BK. Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/81.
Council of Science Editors:
Stuhl BK. Ultracold molecules for the masses: evaporative cooling and magneto-optical trapping. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/phys_gradetds/81
University of Colorado
5.
Benko, Craig Anthony.
Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics.
Degree: PhD, Physics, 2016, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/170
► The extreme ultraviolet (XUV) is a relatively unexplored spectral region for high-resolution laser spectroscopy. Many atomic and molecular systems of fundamental interest lie in…
(more)
▼ The extreme ultraviolet (XUV) is a relatively unexplored spectral region for high-resolution laser spectroscopy. Many atomic and molecular systems of fundamental interest lie in wait of investigation, but the lack of highly coherent sources has forgone the ability to experiment. The XUV frequency comb offers exciting new frontiers for fundamental
physics and measurement science by enabling direct and highly coherent laser access to the XUV. Prior to 2012, our group demonstrated the best levels of phase coherence in the XUV at the 10 MHz level and the most powerful XUV light source originating from high-order harmonic generation with powers of 220
μW/harmonic. The work in this thesis improves upon both of these metrics demonstrating coherence at the 62.5 mHz level (eight orders of magnitude improvement) and power levels approaching 1 mW/harmonic (five times improvement). Our work shows that it is possible to produce XUV light with coherence properties that rival that of visible light using the high-order harmonic generation process.
Leveraging XUV frequency comb technology, we also extend the work to probe strong field
physics in atomic and molecular systems. We use the phase stable light produced during high-order harmonic generation to probe attosecond phenomena in atoms manifested in the intensity dependent dipole phase. We also study strong-field light-matter interactions in molecular systems. Using our femtosecond enhancement cavities, we perform field-free molecular alignment at unprecedented repetition rates. This allows for a sensitive study of the strong-field interaction and allows the high-order harmonic generation process to be performed in an aligned molecular target.
As XUV frequency comb technology continues to mature, further gains in power levels are anticipated. Additional applications in high-resolution spectroscopy, strong-field
physics, solid-state
physics, and laser science will come to fruition.
Advisors/Committee Members: Jun Ye, John L. Hall, Andreas Becker, Markus Raschke, David Jonas.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Benko, C. A. (2016). Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/170
Chicago Manual of Style (16th Edition):
Benko, Craig Anthony. “Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics.” 2016. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/170.
MLA Handbook (7th Edition):
Benko, Craig Anthony. “Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics.” 2016. Web. 02 Mar 2021.
Vancouver:
Benko CA. Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/170.
Council of Science Editors:
Benko CA. Extreme Ultraviolet Frequency Combs for Precision Measurement and Strong-Field Physics. [Doctoral Dissertation]. University of Colorado; 2016. Available from: https://scholar.colorado.edu/phys_gradetds/170
University of Colorado
6.
Blanshan, Eric M.
Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping.
Degree: PhD, Physics, 2014, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/124
► Field-grade atomic clocks capable of primary standard performance in compact physics packages would be of significant value in a variety of applications ranging from…
(more)
▼ Field-grade atomic clocks capable of primary standard performance in compact
physics packages would be of significant value in a variety of applications ranging from network synchronization and secure communications to GPS hold-over and inertial navigation. A cold-atom coherent population trapping (CACPT) clock featuring laser-cooled
87RB atoms and pulsed Ramsey interrogation is a strong candidate for this technology if the principal frequency shifts can be controlled and the performance degradation associated with miniaturization can be overcome. In this thesis, research focused on the development of this type of compact atomic clock is presented. To address the low atom numbers obtained in small cold-atom sources, experiments were performed in which an atomic beam was decelerated with bichromatic stimulated laser forces and loaded into a mm-scale magneto-
optical trap, increasing the atom number by a factor of 12.5x. A CACPT clock using the high-contrast lin||lin
optical interrogation technique was developed and achieved a stability of 7 × 10
-13 after one hour of integration. Doppler shifts in the clock are explained using a simple kinematic model and canceled by interrogating the atoms with a counter-propagating CPT configuration. Finally, a thorough characterization of the AC-stark effect in lin||lin CPT was performed. Observed shifts are explained in terms of contributions from coherent CPT-generating couplings and population transfer effects caused by
optical pumping from incoherent light. Measurements are compared with existing and new theoretical treatments, and a laser configuration is identified that reduces clock drift from light shifts to less than 10
-14 for the current system.
Advisors/Committee Members: Andreas Becker, John Kitching, Neil Ashby, Heather Lewandowski, Y.C. Lee.
Subjects/Keywords: Atomic; Molecular and Optical Physics
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APA (6th Edition):
Blanshan, E. M. (2014). Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/124
Chicago Manual of Style (16th Edition):
Blanshan, Eric M. “Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping.” 2014. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/124.
MLA Handbook (7th Edition):
Blanshan, Eric M. “Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping.” 2014. Web. 02 Mar 2021.
Vancouver:
Blanshan EM. Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/124.
Council of Science Editors:
Blanshan EM. Development of a Compact Cold-Atom Atomic Clock Based on Coherent Population Trapping. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/phys_gradetds/124
College of William and Mary
7.
Kluttz, Kelly Anita.
Studies of polarized and unpolarized helium -3 in the presence of alkali vapor.
Degree: PhD, Physics, 2012, College of William and Mary
URL: https://scholarworks.wm.edu/etd/1539623608
► At the Thomas Jefferson National Accelerator Facility, glass target cells containing a high density of highly polarized 3He nuclei are used in electron scattering experiments…
(more)
▼ At the Thomas Jefferson National Accelerator Facility, glass target cells containing a high density of highly polarized 3He nuclei are used in electron scattering experiments studying the substructure of the neutron. In addition to 3He, these cells contain a small amount of rubidium (Rb), potassium (K), and nitrogen (N2), which facilitate the polarization process. The work presented here represents studies of the interactions between the alkali vapor and 3He nuclei when both are polarized and unpolarized.;Our investigations into the mechanisms responsible for the relaxation of the 3He polarization have measured unusually large polarization losses. In addition, most cells studied exhibited polarization lifetimes much shorter than those typically observed in cells used for scattering experiments. These results suggest there are relaxation mechanisms that depend on whether the cell contains polarized or unpolarized alkali vapor, solid alkali, or no alkali. Previous cell studies have assumed these relaxation mechanisms are independent of the presence of alkali in any form. Modication of the polarization rate equations to include these new relaxation mechanisms are given. Further studies are needed to fully understand the origin of these additional relaxation mechanisms.;Studies of the interactions between 3He and alkali vapor, when both are unpolarized, were motivated by the need to determine the number density of 3He inside sealed cells. The system we have implemented to measure the number density examines the broadening of the absorption profiles of the D1 and D2 lines of Rb and K due to collisions with 3He and N2. However, in order to relate this broadening to the gas density, the value of the velocity-averaged collisional cross-section (broadening coefficient) for the interacting pair of atoms must be known. While the value of the coefficient has been measured for Rb, no data have been published for K interacting with 3He at the high number densities required for scattering experiments. Furthermore, pressure broadening theory predicts a temperature dependence for the coefficients, but very little experimental data has been published. In addition to broadening, a shift in the central frequency is also predicted and has been experimentally verified. We have measured both the broadening and shift of the D1 and D2 lines of Rb and K in the presence of 3He and N2 over a range of number densities and temperatures.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Kluttz, K. A. (2012). Studies of polarized and unpolarized helium -3 in the presence of alkali vapor. (Doctoral Dissertation). College of William and Mary. Retrieved from https://scholarworks.wm.edu/etd/1539623608
Chicago Manual of Style (16th Edition):
Kluttz, Kelly Anita. “Studies of polarized and unpolarized helium -3 in the presence of alkali vapor.” 2012. Doctoral Dissertation, College of William and Mary. Accessed March 02, 2021.
https://scholarworks.wm.edu/etd/1539623608.
MLA Handbook (7th Edition):
Kluttz, Kelly Anita. “Studies of polarized and unpolarized helium -3 in the presence of alkali vapor.” 2012. Web. 02 Mar 2021.
Vancouver:
Kluttz KA. Studies of polarized and unpolarized helium -3 in the presence of alkali vapor. [Internet] [Doctoral dissertation]. College of William and Mary; 2012. [cited 2021 Mar 02].
Available from: https://scholarworks.wm.edu/etd/1539623608.
Council of Science Editors:
Kluttz KA. Studies of polarized and unpolarized helium -3 in the presence of alkali vapor. [Doctoral Dissertation]. College of William and Mary; 2012. Available from: https://scholarworks.wm.edu/etd/1539623608
Embry-Riddle Aeronautical University
8.
Haluska, Nathan.
Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures.
Degree: MSin Engineering Physics, Physical Sciences, 2010, Embry-Riddle Aeronautical University
URL: https://commons.erau.edu/db-theses/76
► In recent years quantum dots (QD) have attracted increasing interest because of their wide variety of revolutionary applications. Such applications include high speed optical…
(more)
▼ In recent years quantum dots (QD) have attracted increasing interest because of their wide variety of revolutionary applications. Such applications include high speed
optical communication lasers, infrared photodetectors, and single photon emitters. One promising immediate application is QD solar cells. Proper analysis of the
optical absorption characteristics in these solar cells requires a rigorous modeling of the electronic structure and
optical properties of semiconductor heterostructures. Our emphasis will be on type III-V semiconductors. Such structures, have a great potential for increasing efficiencies, but they also possess highly degenerate and complex valence band structures. Therefore, we seek to develop a model of spherical QD band structure for type III-V Semiconductor materials, and with such results we obtain the absorption properties of the simulated QDs. We assume stress and strain effects are negligible. We also assume the conduction and spin-orbit bands are treated as distant. We utilize the spherically symmetric, single and multiple band effective mass equations along with previously developed analytical methods to simplify the problem, then we obtain the eigenfunctions and eigenenergies of the QD, and use them to model
optical transitions. We assume a quasi-equilibrium Fermi-Dirac distribution for electrons and holes and obtain the microscopic transition rates and absorption coefficients. Furthermore, we implement this in Matlab with a robust graphical user interface which allows for arbitrary configurations of materials and QD sizes. With this tool, the eigenenergies, eigenfunctions, and absorption coefficients may be calculated.
Advisors/Committee Members: Dr. Bereket H. Berhane, Dr. Gulamabas Sivjee, Dr. John Mathis.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Haluska, N. (2010). Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures. (Masters Thesis). Embry-Riddle Aeronautical University. Retrieved from https://commons.erau.edu/db-theses/76
Chicago Manual of Style (16th Edition):
Haluska, Nathan. “Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures.” 2010. Masters Thesis, Embry-Riddle Aeronautical University. Accessed March 02, 2021.
https://commons.erau.edu/db-theses/76.
MLA Handbook (7th Edition):
Haluska, Nathan. “Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures.” 2010. Web. 02 Mar 2021.
Vancouver:
Haluska N. Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures. [Internet] [Masters thesis]. Embry-Riddle Aeronautical University; 2010. [cited 2021 Mar 02].
Available from: https://commons.erau.edu/db-theses/76.
Council of Science Editors:
Haluska N. Optical Properties of Type III-V Semiconductor Spherical Quantum Dot Heterostructures. [Masters Thesis]. Embry-Riddle Aeronautical University; 2010. Available from: https://commons.erau.edu/db-theses/76
University of Colorado
9.
Arpin, Paul Christopher.
Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation.
Degree: PhD, Physics, 2011, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/51
► High order harmonic generation (HHG) is a source of bright, ultrafast, fully spatially coherent, extreme ultraviolet (EUV) light with applications in ultrafast molecular and…
(more)
▼ High order harmonic generation (HHG) is a source of bright, ultrafast, fully spatially coherent, extreme ultraviolet (EUV) light with applications in ultrafast molecular and materials spectroscopy, element selective ultrafast magnetic dynamics, nano-thermal heat transport and high-resolution imaging. Harmonics have been generated up to a few keV, but the flux has been very low past 100 eV. Thus, applications of HHG have focused on the EUV region. By enhancing the brightness of harmonics at higher energies, we can expand the applications of HHG to the soft x-ray region of the spectrum. The "water window" is a particularly important region of the spectrum for high resolution biological imaging. In this region, between 284 and 540 eV, water is an order of magnitude more transparent than carbon, providing contrast between various biological materials. This thesis presents two methods to improve the brightness of harmonics in the water window. In the first, harmonics were generated from doubly ionized argon, which extended the cutoff photon energy to 540 eV, 200 eV higher than previously demonstrated from argon. The second method used the recently developed mid-infrared phase-matching technique to fully phase match the harmonic process at soft x-ray photon energies up to 540 eV which increased the brightness of harmonics in the water window by three orders of magnitude. This source was then characterized with the first spatial coherence measurement of any compact light source in this spectral range. In the future, this source can be used for high resolution, element specific, coherent imaging in the water window and ultrafast transient absorption spectroscopy in molecules and materials.
Advisors/Committee Members: Henry C. Kapteyn, Margaret M. Murnane, Andreas Becker.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Optics; Physics
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APA (6th Edition):
Arpin, P. C. (2011). Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/51
Chicago Manual of Style (16th Edition):
Arpin, Paul Christopher. “Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation.” 2011. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/51.
MLA Handbook (7th Edition):
Arpin, Paul Christopher. “Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation.” 2011. Web. 02 Mar 2021.
Vancouver:
Arpin PC. Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation. [Internet] [Doctoral dissertation]. University of Colorado; 2011. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/51.
Council of Science Editors:
Arpin PC. Generation and Characterization of Coherent Soft X-Ray Light with High Harmonic Generation. [Doctoral Dissertation]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/phys_gradetds/51
University of Colorado
10.
Spott, Andrew.
Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms.
Degree: PhD, Physics, 2017, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/221
► Perturbative nonlinear optics consists of many powerful predictive theoretical methods, in- cluding the perturbative series of observables related to the interaction of light with…
(more)
▼ Perturbative nonlinear optics consists of many powerful predictive theoretical methods, in- cluding the perturbative series of observables related to the interaction of light with matter. The light intensity limits of such series have been studied in the past for highly nonlinear processes such as above threshold ionization and high harmonic generation. A more recent debate focuses on the limits of applicability of perturbation theory for the nonlinear electrical susceptibility and the nonlinear index of refraction of atoms, which are important parameters to study, for example, for filamentation of laser pulses in nonlinear media. In this thesis we analyze theoretical predictions for the electrical susceptibility of atoms for the transition from the perturbative to the nonperturbative intensity regime. To this end, we apply a numerical basis state method that allows us to perform respective calculations in the framework of perturbation theory as well as using ab-initio methods. The results let us identify the intensity at which the application of perturbation theory breaks down. Furthermore, we provide an analysis of the nonlinear susceptibility as a function of time during the interaction with the laser pulse and find that theoretical predictions are in good agreement with recent experimental data.
Advisors/Committee Members: Andreas Becker, Agnieszka Jaron-Becker, David Jonas, Margaret Murnane, Jose D’incao.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Quantum Physics
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APA (6th Edition):
Spott, A. (2017). Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/221
Chicago Manual of Style (16th Edition):
Spott, Andrew. “Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms.” 2017. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/221.
MLA Handbook (7th Edition):
Spott, Andrew. “Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms.” 2017. Web. 02 Mar 2021.
Vancouver:
Spott A. Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/221.
Council of Science Editors:
Spott A. Perturbative and Ab-Initio Calculations of Electrical Susceptibilities of Atoms. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/phys_gradetds/221
University of Nevada – Las Vegas
11.
Bowen, Kyle Patrick.
A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays.
Degree: PhD, Chemistry and Biochemistry, 2016, University of Nevada – Las Vegas
URL: https://digitalscholarship.unlv.edu/thesesdissertations/2644
► Modelling angular distributions of photoelectrons requires making accurate approximations of both the incoming light and the behavior of bound electrons. The experimental determination of…
(more)
▼ Modelling angular distributions of photoelectrons requires making accurate approximations of both the incoming light and the behavior of bound electrons. The experimental determination of photoelectron angular distributions is crucial to the development of accurate theoretical models governing the light-matter interaction. To date, many models have relied upon the dipole approximation, which assumes a constant electric field as the source of ionization. Despite knowing that the dipole approximation would break down as photon energy increased, the precise limit was unclear. Over the past two decades, a strong case has been made that corrections to the dipole approximation are necessary for accurately describing photoionization using soft x-rays (100 – 1000 eV). This energy region is widely studied, as it has become more readily accessible thanks to third-generation synchrotron radiation facilities.
This work provides experimental evidence for first-order corrections to the dipole approximation, known as nondipole effects, for atoms and molecules, focusing on Xe 3d photoionization, which showcases the role of interchannel coupling in nondipole angular distributions, N 1s photoionization from molecular nitrogen in an attempt to settle a dispute over molecular nondipole effects, and C 1s photoionization from the chiral molecule camphor, which provides the first-ever experimental determination of a theoretically predicted chiral-specific nondipole effect. All of the experiments were performed using electron time-of-flight spectroscopy at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL).
Advisors/Committee Members: Clemens Heske, Dennis W. Lindle, Oliver Hemmers, Balakrishnan Naduvalath, Paul Forster, Bernard Zygelman.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Quantum Physics
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APA (6th Edition):
Bowen, K. P. (2016). A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays. (Doctoral Dissertation). University of Nevada – Las Vegas. Retrieved from https://digitalscholarship.unlv.edu/thesesdissertations/2644
Chicago Manual of Style (16th Edition):
Bowen, Kyle Patrick. “A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays.” 2016. Doctoral Dissertation, University of Nevada – Las Vegas. Accessed March 02, 2021.
https://digitalscholarship.unlv.edu/thesesdissertations/2644.
MLA Handbook (7th Edition):
Bowen, Kyle Patrick. “A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays.” 2016. Web. 02 Mar 2021.
Vancouver:
Bowen KP. A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays. [Internet] [Doctoral dissertation]. University of Nevada – Las Vegas; 2016. [cited 2021 Mar 02].
Available from: https://digitalscholarship.unlv.edu/thesesdissertations/2644.
Council of Science Editors:
Bowen KP. A Case for Chiral Contributions to Nondipole Effects in Photoionization Using Linearly Polarized Soft X-rays. [Doctoral Dissertation]. University of Nevada – Las Vegas; 2016. Available from: https://digitalscholarship.unlv.edu/thesesdissertations/2644
University of Nevada – Las Vegas
12.
Wilde, Scott.
Dispersion of the hyperpolarizability of the carbon tetrachloride molecule.
Degree: MSin Physics, Physics and Astronomy, 2011, University of Nevada – Las Vegas
URL: https://digitalscholarship.unlv.edu/thesesdissertations/1016
► The second hyperpolarizability of a molecule is the microscopic version of the third order susceptibility. Direct measurements of the ratio of the second hyperpolarizability…
(more)
▼ The second hyperpolarizability of a molecule is the microscopic version of the third order susceptibility. Direct measurements of the ratio of the second hyperpolarizability of carbon tetrachloride to diatomic nitrogen are made possible through electric field induced second harmonic generation. Whenever the dispersion of the second hyperpolarizability is not negligible, there should be deviations from Kleinman symmetry. Previous experimental data for second hyperpolarizability of this molecule have only been at two frequencies and theory predicts the zero frequency value. In order to provide for a better extrapolation to zero frequency, additional gas phase measurements of this ratio at
optical frequencies are presented and discussed.
Advisors/Committee Members: David P. Shelton, Chair, Victor H. S. Kwong, Stephen Lepp.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Wilde, S. (2011). Dispersion of the hyperpolarizability of the carbon tetrachloride molecule. (Masters Thesis). University of Nevada – Las Vegas. Retrieved from https://digitalscholarship.unlv.edu/thesesdissertations/1016
Chicago Manual of Style (16th Edition):
Wilde, Scott. “Dispersion of the hyperpolarizability of the carbon tetrachloride molecule.” 2011. Masters Thesis, University of Nevada – Las Vegas. Accessed March 02, 2021.
https://digitalscholarship.unlv.edu/thesesdissertations/1016.
MLA Handbook (7th Edition):
Wilde, Scott. “Dispersion of the hyperpolarizability of the carbon tetrachloride molecule.” 2011. Web. 02 Mar 2021.
Vancouver:
Wilde S. Dispersion of the hyperpolarizability of the carbon tetrachloride molecule. [Internet] [Masters thesis]. University of Nevada – Las Vegas; 2011. [cited 2021 Mar 02].
Available from: https://digitalscholarship.unlv.edu/thesesdissertations/1016.
Council of Science Editors:
Wilde S. Dispersion of the hyperpolarizability of the carbon tetrachloride molecule. [Masters Thesis]. University of Nevada – Las Vegas; 2011. Available from: https://digitalscholarship.unlv.edu/thesesdissertations/1016
University of Nevada – Las Vegas
13.
Howard, John William.
Li+ Ion Transport in Select Lithium-Rich Antiperovskites.
Degree: PhD, Physics and Astronomy, 2014, University of Nevada – Las Vegas
URL: https://digitalscholarship.unlv.edu/thesesdissertations/2269
► Lithium-Rich Antiperovskites (LiRAPs) have been shown to possess relatively high ionic conductivity at room temperature, and become superionic conductors at elevated temperatures. These materials…
(more)
▼ Lithium-Rich Antiperovskites (LiRAPs) have been shown to possess relatively high ionic conductivity at room temperature, and become superionic conductors at elevated temperatures. These materials generally have a stoichiometry Li3BX, where B is a doubly deficient anion, and X is a monovalent anion. Ideally they belong to the high symmetry space group Pm-3m where lithium atoms occupy octahedral corners, B anions occupy octahedral centers, and X anions occupy the interstitial centers between the octahedra. LiRAPs were synthesized using several different methods and characterized by XRD, EIS, DSC, TGA, FTIR, and INS techniques. Chemical analyses were performed to determine the stoichiometries of the base compounds Li3OCl, Li2(OH)Cl, and Li2(OH)Br. Ionic conductivities range from 2 x 10-5 S/cm to 2 x 10-9 S/cm at room temperature, and activation energies of Li+ diffusion range from 0.49 eV to 1.02 eV.
Advisors/Committee Members: Yusheng Zhao, Oliver Tschauner Tschauner, Changfeng Chen, Clemens Heske.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Howard, J. W. (2014). Li+ Ion Transport in Select Lithium-Rich Antiperovskites. (Doctoral Dissertation). University of Nevada – Las Vegas. Retrieved from https://digitalscholarship.unlv.edu/thesesdissertations/2269
Chicago Manual of Style (16th Edition):
Howard, John William. “Li+ Ion Transport in Select Lithium-Rich Antiperovskites.” 2014. Doctoral Dissertation, University of Nevada – Las Vegas. Accessed March 02, 2021.
https://digitalscholarship.unlv.edu/thesesdissertations/2269.
MLA Handbook (7th Edition):
Howard, John William. “Li+ Ion Transport in Select Lithium-Rich Antiperovskites.” 2014. Web. 02 Mar 2021.
Vancouver:
Howard JW. Li+ Ion Transport in Select Lithium-Rich Antiperovskites. [Internet] [Doctoral dissertation]. University of Nevada – Las Vegas; 2014. [cited 2021 Mar 02].
Available from: https://digitalscholarship.unlv.edu/thesesdissertations/2269.
Council of Science Editors:
Howard JW. Li+ Ion Transport in Select Lithium-Rich Antiperovskites. [Doctoral Dissertation]. University of Nevada – Las Vegas; 2014. Available from: https://digitalscholarship.unlv.edu/thesesdissertations/2269
Purdue University
14.
Mosquera-Tabares, Martin A.
Theory of density functionals.
Degree: PhD, Chemistry, 2014, Purdue University
URL: https://docs.lib.purdue.edu/open_access_dissertations/336
► Density functional theory is an alternative quantum mechanical theory that offers simple ways of performing calculations of the electronic properties of matter. Many different…
(more)
▼ Density functional theory is an alternative quantum mechanical theory that offers simple ways of performing calculations of the electronic properties of matter. Many different methods derive from density functional theory. The most appealing for its simplicity and rigor is the theory of Kohn and Sham. In this thesis I propose new methods in density-functional theory that are helpful to address some important problems in the application of the local-density approximation within Kohn-Sham DFT to the analysis of ground-states and dynamical properties of electronic systems.
Advisors/Committee Members: Adam Wasserman, Adam Wasserman, Suzzane C. Bart, Sabre Kais, Garth J. Simpson.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Mosquera-Tabares, M. A. (2014). Theory of density functionals. (Doctoral Dissertation). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_dissertations/336
Chicago Manual of Style (16th Edition):
Mosquera-Tabares, Martin A. “Theory of density functionals.” 2014. Doctoral Dissertation, Purdue University. Accessed March 02, 2021.
https://docs.lib.purdue.edu/open_access_dissertations/336.
MLA Handbook (7th Edition):
Mosquera-Tabares, Martin A. “Theory of density functionals.” 2014. Web. 02 Mar 2021.
Vancouver:
Mosquera-Tabares MA. Theory of density functionals. [Internet] [Doctoral dissertation]. Purdue University; 2014. [cited 2021 Mar 02].
Available from: https://docs.lib.purdue.edu/open_access_dissertations/336.
Council of Science Editors:
Mosquera-Tabares MA. Theory of density functionals. [Doctoral Dissertation]. Purdue University; 2014. Available from: https://docs.lib.purdue.edu/open_access_dissertations/336
University of Central Florida
15.
Cheng, Yan.
Attosecond Transient Absorption Spectroscopy of Atoms and Molecules.
Degree: 2015, University of Central Florida
URL: https://stars.library.ucf.edu/etd/5151
► One of the most fundamental goals of attosecond science is to observe and to control the dynamic evolutions of electrons in matter. The attosecond…
(more)
▼ One of the most fundamental goals of attosecond science is to observe and to control the dynamic evolutions of electrons in matter. The attosecond transient absorption spectroscopy is a powerful tool to utilize attosecond pulse to measure electron dynamics in quantum systems directly. In this work, isolated single attosecond pulses are used to probe electron dynamics in atoms and to study dynamics in hydrogen molecules using the attosecond transient absorption spectroscopy technique. The target atom/molecule is first pumped to excited states and then probed by a subsequent attosecond extreme ultraviolet (XUV) pulse or by a near infrared (NIR) laser pulse. By measuring the absorbed attosecond XUV pulse spectrum, the ultrafast electron correlation dynamics can be studied in real time. The quantum processes that can be studied using the attosecond transient absorption spectroscopy include the AC stark shift, multi-photon absorption, intermediate states of atoms, autoionizing states, and transitions of vibrational states in molecules. In all experiments, the absorption changes as a function of the time delay between the attosecond XUV probe pulse and the dressing NIR laser pulse, on a time scale of sub-cycle laser period, which reveals attosecond electron dynamics. These experiments demonstrate that the attosecond transient absorption spectroscopy can be performed to study and control electronic and nuclear dynamics in quantum systems with high temporal and spectral resolution, and it opens door for the study of electron dynamics in large molecules and other more complex systems.
Advisors/Committee Members: Chang, Zenghu.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Cheng, Y. (2015). Attosecond Transient Absorption Spectroscopy of Atoms and Molecules. (Doctoral Dissertation). University of Central Florida. Retrieved from https://stars.library.ucf.edu/etd/5151
Chicago Manual of Style (16th Edition):
Cheng, Yan. “Attosecond Transient Absorption Spectroscopy of Atoms and Molecules.” 2015. Doctoral Dissertation, University of Central Florida. Accessed March 02, 2021.
https://stars.library.ucf.edu/etd/5151.
MLA Handbook (7th Edition):
Cheng, Yan. “Attosecond Transient Absorption Spectroscopy of Atoms and Molecules.” 2015. Web. 02 Mar 2021.
Vancouver:
Cheng Y. Attosecond Transient Absorption Spectroscopy of Atoms and Molecules. [Internet] [Doctoral dissertation]. University of Central Florida; 2015. [cited 2021 Mar 02].
Available from: https://stars.library.ucf.edu/etd/5151.
Council of Science Editors:
Cheng Y. Attosecond Transient Absorption Spectroscopy of Atoms and Molecules. [Doctoral Dissertation]. University of Central Florida; 2015. Available from: https://stars.library.ucf.edu/etd/5151
University of Central Florida
16.
Shafai Erfani, Ghazal.
Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles.
Degree: 2015, University of Central Florida
URL: https://stars.library.ucf.edu/etd/5152
► The main objective of this dissertation is to provide better understanding of the atomic configurations, electronic structure, vibrational properties, and thermodynamics of transition metal…
(more)
▼ The main objective of this dissertation is to provide better understanding of the atomic configurations, electronic structure, vibrational properties, and thermodynamics of transition metal nanoparticles and evaluate the intrinsic (i.e. size and shape) and extrinsic (i.e. ligands, adsorbates, and support) effects on the aforementioned properties through a simulational approach. The presented research provides insight into better understanding of the morphological changes of the nanoparticles that are brought about by the intrinsic factors as well as the extrinsic ones. The preference of certain ligands to stabilize specific sizes of nanoparticles is investigated. The intrinsic and extrinsic effects on the electronic structure of the nanoparticles are presented. The physical and chemical properties of the nanoparticles are evaluated through better understanding of the above effects on the experimentally observed properties as well as the applied techniques. The unexpected experimental results are tested and interpreted by deconvolution of the affecting factors. The application of Debye model to nanoparticles is tested and its shortcomings at nanoscale are discussed. Predictions which can provide insight into intelligent choice of candidates to cater to certain properties are provided. The results of this thesis can be used in the future in design and engineering of functionalized materials. We use ab initio calculations based on Density Functional Theory (DFT) to obtain information about the energetics, atomic configuration, and electronic structure of the nanoparticles. Ab initio Molecular Dynamics (MD) is used to study the evolution of the structures of the nanoparticles. To calculate vibrational frequencies, the finite displacement method is employed.
Advisors/Committee Members: Rahman, Talat S..
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Shafai Erfani, G. (2015). Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles. (Doctoral Dissertation). University of Central Florida. Retrieved from https://stars.library.ucf.edu/etd/5152
Chicago Manual of Style (16th Edition):
Shafai Erfani, Ghazal. “Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles.” 2015. Doctoral Dissertation, University of Central Florida. Accessed March 02, 2021.
https://stars.library.ucf.edu/etd/5152.
MLA Handbook (7th Edition):
Shafai Erfani, Ghazal. “Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles.” 2015. Web. 02 Mar 2021.
Vancouver:
Shafai Erfani G. Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles. [Internet] [Doctoral dissertation]. University of Central Florida; 2015. [cited 2021 Mar 02].
Available from: https://stars.library.ucf.edu/etd/5152.
Council of Science Editors:
Shafai Erfani G. Theoretical and Computational Studies of the electronic, Structural, Vibrational, and Thermodynamic Properties of Transition Metal Nanoparticles. [Doctoral Dissertation]. University of Central Florida; 2015. Available from: https://stars.library.ucf.edu/etd/5152
University of Central Florida
17.
Malone, Walter.
A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces.
Degree: 2019, University of Central Florida
URL: https://stars.library.ucf.edu/etd/6344
► With the ever growing number of proposed desnity functional theory (DFT) functionals it becomes necessary to thoroughly screen any new method to determine its merit.…
(more)
▼ With the ever growing number of proposed desnity functional theory (DFT) functionals it becomes necessary to thoroughly screen any new method to determine its merit. Especially relevant methods include a proper description of the van der Waals (vdW) interaction, which can prove vital to a correct description of a myriad of systems of technological importance. The first part of this dissertation explores the utility of several vdW-inclusive DFT functionals including optB86b-vdW, optB88-vdW, optPBE-vdW, revPBE-vdW, rPW86-vdW2, and SCAN+rVV10 by applying them to model systems of small organic molecules, pyridine and thiophene, on transition metal surfaces. Overall, we find the optB88-vdW functional gives the best, most balanced description of both thiophene and pyridine on transition metal surfaces while revPBE-vdW, rPW86-vdW2, and SCAN+rVV10 functionals perform especially poorly for these systems. In the second part of this dissertation we change our focus to potential applications of DFT. Specifically, we study the hydrodesulfurization (HDS) process and molecules that could be used in molecular electronics. The removal of sulfur containing molecules from petrochemicals through HDS is an exceptionally important process economically, and the field of molecular electronics is rapidly developing with hopes of competing with and replacing their silicon analogues. First we investigate the hydrodesulfurization of thiophene. In this dissertation we manage to map the HDS rate of thiophene in realistic reaction conditions to the charge transfer and adsorption energy of thiophene on bare transition metal surfaces in hopes of predicting ever more active HDS catalysis. Finally we look at the adsorption of polythiophenes and 5,14-dihydro-5,7,12,14-tetraazapentacene (DHTAP) on Au(111) and Cu(110). We find that polythiophenes may dissociate of Au(111), presenting an issue for their use in molecular electronics. DHTAP, in contrast, proves to a suitable candidate for use practical devices.
Advisors/Committee Members: Kara, Abdelkader.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Physics
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APA (6th Edition):
Malone, W. (2019). A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces. (Doctoral Dissertation). University of Central Florida. Retrieved from https://stars.library.ucf.edu/etd/6344
Chicago Manual of Style (16th Edition):
Malone, Walter. “A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces.” 2019. Doctoral Dissertation, University of Central Florida. Accessed March 02, 2021.
https://stars.library.ucf.edu/etd/6344.
MLA Handbook (7th Edition):
Malone, Walter. “A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces.” 2019. Web. 02 Mar 2021.
Vancouver:
Malone W. A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces. [Internet] [Doctoral dissertation]. University of Central Florida; 2019. [cited 2021 Mar 02].
Available from: https://stars.library.ucf.edu/etd/6344.
Council of Science Editors:
Malone W. A Theoretical Investigation of Small Organic Molecules on Transition Metal Surfaces. [Doctoral Dissertation]. University of Central Florida; 2019. Available from: https://stars.library.ucf.edu/etd/6344
University of Colorado
18.
Lester, Brian James.
Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays.
Degree: PhD, Physics, 2016, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/189
► In this thesis, I describe early experiments with a new platform that harnesses control over the full quantum state of individual 87Rb atoms to…
(more)
▼ In this thesis, I describe early experiments with a new platform that harnesses control over the full quantum state of individual
87Rb atoms to study out-of-equilibrium states of a few atoms placed in tailored
optical potentials. We employ an enhanced loading technique that fills each well in 90% of loading attempts, image the configuration of the atoms, and then perform Raman sideband cooling that results in a 90% three-dimensional ground state fraction. Then, after initializing the spin of each atom, we can reconfigure the traps to initialize dynamics in a final
optical potential of interest. For example, we can form a double well potential and observe the quantum interference of two atoms tunneling between the wells. Additionally, we have demonstrated the ability to coherently transfer atoms between wells and, by preparing two atoms in opposite spin states, have observed spin-exchange oscillations that periodically entangle the two atoms. I will also discuss plans and ongoing work to combine these capabilities with new techniques to gain more information from systems containing more atoms. In such systems, we wish to study how the spin-motional coupling of independently prepared atoms, in the presence of interactions, will lead to complex dynamics, such as in the Kondo lattice model.
Advisors/Committee Members: Cindy A. Regal, Ana M. Rey, Emanuel H. Knill, Dana Z. Anderson, Robert R. McLeod.
Subjects/Keywords: Quantum gas; single atom; optical tweezers; Kondo; Atomic, Molecular and Optical Physics; Physics; Quantum Physics
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APA (6th Edition):
Lester, B. J. (2016). Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/189
Chicago Manual of Style (16th Edition):
Lester, Brian James. “Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays.” 2016. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/189.
MLA Handbook (7th Edition):
Lester, Brian James. “Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays.” 2016. Web. 02 Mar 2021.
Vancouver:
Lester BJ. Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/189.
Council of Science Editors:
Lester BJ. Atom-By-Atom Control and Readout for Studying Spin-Motional Dynamics and Entanglement in Neutral Atom Arrays. [Doctoral Dissertation]. University of Colorado; 2016. Available from: https://scholar.colorado.edu/phys_gradetds/189
College of William and Mary
19.
Ziltz, Austin R.
Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials.
Degree: PhD, Physics, 2015, College of William and Mary
URL: https://scholarworks.wm.edu/etd/1539624008
► In this dissertation we study the development of microwave and RF near-field potentials for use with atom chip trapped atomic gases. These potentials are inherently…
(more)
▼ In this dissertation we study the development of microwave and RF near-field potentials for use with atom chip trapped atomic gases. These potentials are inherently spin-dependent, able to target individual spin states simultaneously. In contrast with traditional atom chip potentials, these RF traps can be operated at arbitrary bias magnetic field strengths and thus be combined with magnetic Feshbach resonances. Furthermore, these potentials can strongly suppress the potential roughness that plagues traditional atom chip potentials. We present a dual chamber atom chip apparatus for generating ultracold 87Rb and 39K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 104 87Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold 39K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multi coil magnetic transport system, and the atom chip. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Condensed Matter Physics; Physics
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APA (6th Edition):
Ziltz, A. R. (2015). Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials. (Doctoral Dissertation). College of William and Mary. Retrieved from https://scholarworks.wm.edu/etd/1539624008
Chicago Manual of Style (16th Edition):
Ziltz, Austin R. “Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials.” 2015. Doctoral Dissertation, College of William and Mary. Accessed March 02, 2021.
https://scholarworks.wm.edu/etd/1539624008.
MLA Handbook (7th Edition):
Ziltz, Austin R. “Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials.” 2015. Web. 02 Mar 2021.
Vancouver:
Ziltz AR. Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials. [Internet] [Doctoral dissertation]. College of William and Mary; 2015. [cited 2021 Mar 02].
Available from: https://scholarworks.wm.edu/etd/1539624008.
Council of Science Editors:
Ziltz AR. Ultracold rubidium and potassium system for atom chip-based microwave and RF potentials. [Doctoral Dissertation]. College of William and Mary; 2015. Available from: https://scholarworks.wm.edu/etd/1539624008
The Ohio State University
20.
Lai, Yu Hang.
Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields.
Degree: PhD, Physics, 2018, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1514852456303011
► Strong field atomic physics is the study of the interaction between an atom and an intense laser pulse such that the field strength is ``not-so-small"…
(more)
▼ Strong field atomic
physics is the study of the
interaction between an atom and an intense laser pulse such that
the field strength is ``not-so-small" compared to an atomic unit
(50 V/\AA) and so it could not be treated as just a perturbation to
the atomic system. Depending upon the ionization potential of the
target, typical laser intensity required to reach this regime
ranges from ∼ 10 to 1000 TW/cm
2 (the corresponding peak
field strength : ∼0.017 - 0.17 V/\AA). In the low frequency
limit, the photoionization process can be interpreted as a
tunneling process in which the atomic potential is ``tilted" by the
laser field allowing the electron to escape via quantum tunneling.
The escaped electron wavepacket quivers in the strong laser field
whose kinetic energy is characterized by the ponderomotive energy
U
p which is proportional to the laser intensity and the square
of the wavelength. Electron recollision happens when the ionized
electron is driven back towards its parent ion by the laser field
and it leads to numerous intriguing phenomena such as high-order
above-threshold ionization, non-sequential ionization and
high-order harmonic generation. While most of the early experiments
were performed in the near-infrared (NIR)(0.8 or 1 μm)
wavelengths, an important advance over the last decade has been the
emergence of intense mid-infrared (MIR)(∼ 2-4 μm) sources.
The quadratic scaling of U
p with wavelength benefits the study
of recollision-driven phenomena and also enables the exploration of
strong field interaction deep in the tunneling regime. In addition,
the MIR regime is of particular interest for studying molecules due
to the presence of vibrational resonances. In this dissertation, we
explore several strong field phenomena in atoms and molecules with
near and mid infrared fields, including:1. A comprehensive
experimental benchmarking of strong field atomic ionization
theories. We performed a comparative study between experiment and
theories of the total intensity-dependent ionization yield for
different atom species at different laser wavelengths (0.4 - 4
μm) at linear and circular polarizations in order to investigate
the applicability of two commonly used strong field ionization
theories, Perelomov, Popov and Terent’ev (PPT) and Ammosov, Delone
and Krainov (ADK) models. 2. Ionization and fragmentation of
methane in vibrationally resonant MIR fields. We measured the mass
spectra of fragments of methane irradiated by MIR fields which
cover the resonant frequency range of the C-H bond stretching mode
vibration (3.2 - 3.5 μm). We observed significant enhancement
in ionization and dissociation rate at resonant wavelengths
compared with non-resonant wavelengths. 3. Electron recollision in
tunnel ionization of C
60 fullerenes in MIR fields. From the
``soft" recollision for low energy electrons we found an unexpected
suppression of the ``low-energy structure” which might be
attributed to the induced dipole field; from the ``hard"
recollision for high energy electrons we…
Advisors/Committee Members: DiMauro, Louis (Advisor).
Subjects/Keywords: Physics; Atomic, molecular and optical physics; Strong field physics; Ultrafast laser
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APA (6th Edition):
Lai, Y. H. (2018). Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1514852456303011
Chicago Manual of Style (16th Edition):
Lai, Yu Hang. “Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields.” 2018. Doctoral Dissertation, The Ohio State University. Accessed March 02, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1514852456303011.
MLA Handbook (7th Edition):
Lai, Yu Hang. “Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields.” 2018. Web. 02 Mar 2021.
Vancouver:
Lai YH. Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields. [Internet] [Doctoral dissertation]. The Ohio State University; 2018. [cited 2021 Mar 02].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1514852456303011.
Council of Science Editors:
Lai YH. Strong Field Phenomena in Atoms and Molecules from Near to
MidInfrared Laser Fields. [Doctoral Dissertation]. The Ohio State University; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1514852456303011
University of Oxford
21.
Stephenson, Laurent.
Entanglement between nodes of a quantum network.
Degree: PhD, 2020, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:5066d87a-55e8-4fd5-b5b8-df1878af97a8
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808314
► Quantum devices are rapidly gaining momentum as a technology that will induce a paradigm shift in computing, communication and cryptography. Trapped ion qubits are one…
(more)
▼ Quantum devices are rapidly gaining momentum as a technology that will induce a paradigm shift in computing, communication and cryptography. Trapped ion qubits are one of the leading candidates for implementing a quantum computer, having previously demonstrated all of the required criteria. Local gate fidelities between ions exceed those for all other platforms, but the total number of ions in a trap is limited by unavoidable issues – one possibility for scaling the ion trap quantum processor is to create entanglement between ions in separate traps via single photons. The work in this thesis demonstrates the generation of remote entanglement between ions at high fidelity and rate, paving the way towards protocols using multiple entangled pairs for computations. We describe the construction from scratch of a twin-trap apparatus designed to entangle separated ions. We demonstrate the entanglement of strontium ions in traps separated by ∼ 2 m by swapping entanglement from single photons emitted by the 88Sr+ ions. A novel photon collection geometry is used, maximising the entanglement between the ion and photon without impeding optical access for standard ion trap laser beam geometries. The Bell state fidelity of the ion-photon state, which is itself a valuable entanglement resource for blind computation, is at least 97.70(12) % in either trap, with entangled pairs detected at a rate of at least 3.98 × 103 s−1. The remote ion-ion Bell state fidelity is 94.0(5) %, and is generated at a rate of 182 s−1, representing the highest fidelity remote entanglement reported in ions by a large margin, at a rate more than an order of magnitude faster than previous experiments. The two identical trap systems are designed with capabilities beyond those demonstrated here. We can co-trap 88Sr+ and 43Ca+ in a microfabricated trap suitable for local ion transport operations, opening up the possibility of performing distillation of remote entanglement in the same apparatus. Entanglement distillation can be used to make remote entanglement with similar fidelity to local operations, and would represent a significant step towards a fully scalable ion trap quantum computer architecture.
Subjects/Keywords: Quantum theory; Atomic, Molecular and Optical Physics
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APA (6th Edition):
Stephenson, L. (2020). Entanglement between nodes of a quantum network. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:5066d87a-55e8-4fd5-b5b8-df1878af97a8 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808314
Chicago Manual of Style (16th Edition):
Stephenson, Laurent. “Entanglement between nodes of a quantum network.” 2020. Doctoral Dissertation, University of Oxford. Accessed March 02, 2021.
http://ora.ox.ac.uk/objects/uuid:5066d87a-55e8-4fd5-b5b8-df1878af97a8 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808314.
MLA Handbook (7th Edition):
Stephenson, Laurent. “Entanglement between nodes of a quantum network.” 2020. Web. 02 Mar 2021.
Vancouver:
Stephenson L. Entanglement between nodes of a quantum network. [Internet] [Doctoral dissertation]. University of Oxford; 2020. [cited 2021 Mar 02].
Available from: http://ora.ox.ac.uk/objects/uuid:5066d87a-55e8-4fd5-b5b8-df1878af97a8 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808314.
Council of Science Editors:
Stephenson L. Entanglement between nodes of a quantum network. [Doctoral Dissertation]. University of Oxford; 2020. Available from: http://ora.ox.ac.uk/objects/uuid:5066d87a-55e8-4fd5-b5b8-df1878af97a8 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808314
College of William and Mary
22.
Phillips, Nathaniel Blair.
Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor.
Degree: PhD, Physics, 2011, College of William and Mary
URL: https://scholarworks.wm.edu/etd/1539623589
► The recent prospect of efficient, reliable, and secure quantum communication relies on the ability to coherently and reversibly map nonclassical states of light onto long-lived…
(more)
▼ The recent prospect of efficient, reliable, and secure quantum communication relies on the ability to coherently and reversibly map nonclassical states of light onto long-lived atomic states. A promising technique that accomplishes this employs Electromagnetically Induced Transparency (EIT), in which a strong classical control field modifies the optical properties of a weak signal field in such a way that a previously opaque medium becomes transparent to the signal field. The accompanying steep dispersion in the index of refraction allows for pulses of light to be decelerated, then stored as an atomic excitation, and later retrieved as a photonic mode. This dissertation presents the results of investigations into methods for optimizing the memory efficiency of this process in an ensemble of hot Rb atoms. We have experimentally demonstrated the effectiveness of two protocols for yielding the best memory efficiency possible at a given atomic density. Improving memory efficiency requires operation at higher optical depths, where undesired effects such as four-wave mixing (FWM) become enhanced and can spontaneously produce a new optical mode (Stokes field). We present the results of experimental and theoretical investigations of the FWM-EIT interaction under continuous-wave (cw), slow light, and stored light conditions. In particular, we provide evidence that indicates that while a Stokes field is generated upon retrieval of the signal field, any information originally encoded in a seeded Stokes field is not independently preserved during the storage process. We present a simple model that describes the propagation dynamics and provides an intuitive description of the EIT-FWM process.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Optics
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APA (6th Edition):
Phillips, N. B. (2011). Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor. (Doctoral Dissertation). College of William and Mary. Retrieved from https://scholarworks.wm.edu/etd/1539623589
Chicago Manual of Style (16th Edition):
Phillips, Nathaniel Blair. “Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor.” 2011. Doctoral Dissertation, College of William and Mary. Accessed March 02, 2021.
https://scholarworks.wm.edu/etd/1539623589.
MLA Handbook (7th Edition):
Phillips, Nathaniel Blair. “Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor.” 2011. Web. 02 Mar 2021.
Vancouver:
Phillips NB. Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor. [Internet] [Doctoral dissertation]. College of William and Mary; 2011. [cited 2021 Mar 02].
Available from: https://scholarworks.wm.edu/etd/1539623589.
Council of Science Editors:
Phillips NB. Slow and stored light under conditions of electromagnetically induced transparency and four wave mixing in an atomic vapor. [Doctoral Dissertation]. College of William and Mary; 2011. Available from: https://scholarworks.wm.edu/etd/1539623589
Embry-Riddle Aeronautical University
23.
Ingvason, Guttormur Arnar.
Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer.
Degree: MSin Aerospace Engineering, Aerospace Engineering, 2013, Embry-Riddle Aeronautical University
URL: https://commons.erau.edu/edt/82
► The aerospace industry is interested in increasing the strength while reducing the weight of carbon fiber composite materials. Adding single walled carbon nanotubes (SWCNT)…
(more)
▼ The aerospace industry is interested in increasing the strength while reducing the weight of carbon fiber composite materials. Adding single walled carbon nanotubes (SWCNT) to a polymer matrix can achieve that goal by improving delamination properties of the composite. Due to the complexity of polymer molecules and the curing process, few 3-D Molecular Dynamics simulations of a polymer-SWCNT composite have been run. Our model runs on the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS), with a COMPASS (Condensed phase Optimized Molecular Potential for Atomistic Simulations Studies) potential to represent the interactions between the atoms of the polymer and the SWCNT. This potential includes non-bonded interactions (9-6 Lennard-Jones), bond interaction (class2), angles (class2) and dihedrals (class2) to create a molecular dynamics model for single-walled carbon nanotubes and EPON 862/DETDA (Diethyltoluenediamine) polymer matrix. Two simulations were performed in order to test the implementation of the potential. The first one is a tensile test on a SWCNT, leading to a Young's modulus of 1.4 TPa at 300K. The second one is a pull-out test of a SWCNT from an originally uncured EPON 862/DETDA matrix.
Subjects/Keywords: Aerospace Engineering; Atomic, Molecular and Optical Physics
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APA (6th Edition):
Ingvason, G. A. (2013). Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer. (Masters Thesis). Embry-Riddle Aeronautical University. Retrieved from https://commons.erau.edu/edt/82
Chicago Manual of Style (16th Edition):
Ingvason, Guttormur Arnar. “Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer.” 2013. Masters Thesis, Embry-Riddle Aeronautical University. Accessed March 02, 2021.
https://commons.erau.edu/edt/82.
MLA Handbook (7th Edition):
Ingvason, Guttormur Arnar. “Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer.” 2013. Web. 02 Mar 2021.
Vancouver:
Ingvason GA. Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer. [Internet] [Masters thesis]. Embry-Riddle Aeronautical University; 2013. [cited 2021 Mar 02].
Available from: https://commons.erau.edu/edt/82.
Council of Science Editors:
Ingvason GA. Molecular Dynamics Model of Carbon Nanotubes in EPON 862/DETDA Polymer. [Masters Thesis]. Embry-Riddle Aeronautical University; 2013. Available from: https://commons.erau.edu/edt/82
University of Colorado
24.
Stutz, Russell.
Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions.
Degree: PhD, Physics, 2010, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/20
► Permanent electric dipole moments have been the subject of experimental investigation for the past sixty years, as they entail the breaking of fundamental symmetries…
(more)
▼ Permanent electric dipole moments have been the
subject of experimental investigation for the past sixty years, as they entail the breaking of fundamental symmetries and provide a sensitive probe for
physics beyond the Standard Model. This thesis describes an experiment aimed at measuring the electron electric dipole moment (eEDM) using trapped molecular ions. The
3Δ
1 level of certain diatomic ions are desirable in eEDM searches due to their high polarizability, large eEDM enhancement factor, and relative insensitivity to magnetic fields. Ions allow for simple trapping and long interrogation times, but require a time-varying electric bias field in order to probe the eEDM.
I will discuss the criteria for molecular ions in our experiment and our current candidates. A laser-ablation supersonic-expansion beam source has been developed to create and cool molecular ions. These ions have been loaded into a linear rf Paul trap and alternative photoionization methods for state-selective ion creation have been tested. Various experimental methods for performing the necessary spin resonance measurement are discussed. Sources of both decoherence and systematic errors have been identified and estimated. The experiment described in this thesis should be capable of a factor of 30 improvement on the current limit of the eEDM.
Advisors/Committee Members: Eric A. Cornell, Jun Ye, John Bohn.
Subjects/Keywords: Electron; Atomic, Molecular and Optical Physics; Optics
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APA (6th Edition):
Stutz, R. (2010). Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/20
Chicago Manual of Style (16th Edition):
Stutz, Russell. “Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions.” 2010. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/20.
MLA Handbook (7th Edition):
Stutz, Russell. “Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions.” 2010. Web. 02 Mar 2021.
Vancouver:
Stutz R. Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions. [Internet] [Doctoral dissertation]. University of Colorado; 2010. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/20.
Council of Science Editors:
Stutz R. Towards Measuring the Electron Electric Dipole Moment Using Trapped Molecular Ions. [Doctoral Dissertation]. University of Colorado; 2010. Available from: https://scholar.colorado.edu/phys_gradetds/20
University of Colorado
25.
Cumby, Tyler Dunnington.
Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers.
Degree: PhD, Physics, 2012, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/69
► This thesis presents experiments exploring Feshbach molecules and Efimov trimers in an ultracold Bose-Fermi atomic gas mixture of 40K and 87Rb. These bound states…
(more)
▼ This thesis presents experiments exploring Feshbach molecules and Efimov trimers in an ultracold Bose-Fermi atomic gas mixture of 40K and 87Rb. These bound states are accessed via scattering resonances, called Fano-Feshbach resonances, which arise as a consequence of a bound state being tuned through degeneracy with the threshold energy of colliding atoms. In addition to allowing the tunability of interactions, the Fano-Feshbach resonance allows for a weakly bound molecule state, called the Feshbach molecule state, to be populated. The efficiency of conversion to the Feshbach molecule state depends upon the rate with which the bound state energy is swept through degeneracy with atomic threshold energy. In regions of large scattering lengths, three-body bound states, called Efimov states, also influence inelastic Bose-Bose-Fermi collisions and boson+molecule collisions in our system. The work presented in this thesis utilizes a magnetically tunable Fano-Feshbach resonance to study Feshbach molecule creation in the perturbative limit (the limit of fast magnetic-field sweeps) and the saturated limit (the limit of slow sweeps), where a phenomenological model is applied to understand the conversion efficiency as well as the quantum degeneracy of the molecules. In addition, I present a study of boson+molecule collision rates and Bose-Bose-Fermi collision rates in order to observe signatures of Efimov states and compare against results in the gas mixture
41K-
87Rb to address the question of universality of the three-body parameter in heteronuclear gas mixtures.
Advisors/Committee Members: Deborah Jin, Eric Cornell, John Bohn, Heather Lewandowski, W. Carl Lineberger.
Subjects/Keywords: Efimov; Feshbach; Atomic, Molecular and Optical Physics
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APA ·
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MLA ·
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APA (6th Edition):
Cumby, T. D. (2012). Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/69
Chicago Manual of Style (16th Edition):
Cumby, Tyler Dunnington. “Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers.” 2012. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/69.
MLA Handbook (7th Edition):
Cumby, Tyler Dunnington. “Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers.” 2012. Web. 02 Mar 2021.
Vancouver:
Cumby TD. Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers. [Internet] [Doctoral dissertation]. University of Colorado; 2012. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/69.
Council of Science Editors:
Cumby TD. Exploring Few-body Scattering Resonances in a Bose-Fermi Mixture: from Feshbach Dimers to Efimov Trimers. [Doctoral Dissertation]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/phys_gradetds/69
University of Pennsylvania
26.
Zhang, Shaoqing.
Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments.
Degree: 2013, University of Pennsylvania
URL: https://repository.upenn.edu/edissertations/823
► Solvents play an important role in association and assembly of molecules. Here we studied solvent effects on proteins and organic chemicals in different contexts. First,…
(more)
▼ Solvents play an important role in association and assembly of molecules. Here we studied solvent effects on proteins and organic chemicals in different contexts. First, X-ray crystal structures show that helix dimers in membrane- and water-soluble proteins have distinct behaviors in packing and sequence selection. Transmembrane dimers are stabilized by compact packing and hydrogen bonding between small residues. Meanwhile, water-soluble dimers utilize hydrophobic residues for packing irrespective of the size of the interface and tight dimers are rare. Secondly, we apply the results learned above to a complex system in which a designed protein binds to single-walled carbon-nanotube in aqueous environments. Previous designs of the hexameric helical bundles utilized leucine and alanine residues to make two distinct helix-helix interfaces. Our molecular dynamics simulations showed that the alanine-comprising interface is much more labile than the leucine-comprising one. This result can be interpreted by the scarcity of tight soluble helix dimers as mentioned above. Thus more stable modular helix-helix interfaces have to be employed to design peptides binding to carbon-nanotubes with higher affinities. Lastly, we describe a serendipitous discovery of the crystalline framework structure by an amphiphilic triarylamide foldamer. Foldamers are peptide-like polymers of non-natural monomers arranged in defined sequence and chain length that are able to adopt protein-like secondary and tertiary structures. In contrast with traditional metal-organic and organic frameworks, which exploit strong directional coordination and hydrogen bonding for assembly in organic solvents, the crystal herein is built up from a combination of noncovalent hydrophobic, hydrogen-bonded, and electrostatic interactions in aqueous solution. The structure is in honeycomb geometry with each cubicle as a truncated octahedron. A new supramolecular synthon, in which hydrogen bonding and π-π stacking are encompassed, was discovered in the crystal structure. Through NMR experiments we probed the oligomeric states of the foldamer in the early stages prior to crystallization. The hierarchic crystal structure was discussed in terms of supramolecular synthons in crystal engineering.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Bioinformatics; Chemistry
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APA (6th Edition):
Zhang, S. (2013). Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/823
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):
Zhang, Shaoqing. “Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments.” 2013. Thesis, University of Pennsylvania. Accessed March 02, 2021.
https://repository.upenn.edu/edissertations/823.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhang, Shaoqing. “Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments.” 2013. Web. 02 Mar 2021.
Vancouver:
Zhang S. Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments. [Internet] [Thesis]. University of Pennsylvania; 2013. [cited 2021 Mar 02].
Available from: https://repository.upenn.edu/edissertations/823.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhang S. Association of Protein Helices and Assembly of Foldamers: Stories in Membrane and Aqueous Environments. [Thesis]. University of Pennsylvania; 2013. Available from: https://repository.upenn.edu/edissertations/823
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Purdue University
27.
Hoehn, Ross Douglas.
Quantum mechanics in complex systems.
Degree: PhD, Mathematics, 2014, Purdue University
URL: https://docs.lib.purdue.edu/open_access_dissertations/287
► This document should be considered in its separation; there are three distinct topics contained within and three distinct chapters within the body of works.…
(more)
▼ This document should be considered in its separation; there are three distinct topics contained within and three distinct chapters within the body of works. In a similar fashion, this abstract should be considered in three parts. Firstly, we explored the existence of multiply-charged atomic ions by having developed a new set of dimensional scaling equations as well as a series of relativistic augmentations to the standard dimensional scaling procedure and to the self-consistent field calculations. Secondly, we propose a novel method of predicting drug efficacy in hopes to facilitate the discovery of new small molecule therapeutics by modeling the agonist-protein system as being similar to the process of Inelastic Electron Tunneling Spectroscopy. Finally, we facilitate the instruction in basic quantum mechanical topics through the use of quantum games; this method of approach allows for the generation of exercises with the intent of conveying the fundamental concepts within a first year quantum mechanics classroom. Furthermore, no to be mentioned within the body of the text, yet presented in appendix form, certain works modeling the proliferation of cells types within the confines of man-made lattices for the purpose of facilitating artificial vascular transplants. ^ In Chapter 2, we present a theoretical framework which describes multiply-charged atomic ions, their stability within super-intense laser fields, also lay corrections to the systems due to relativistic effects. Dimensional scaling calculations with relativistic corrections for systems: H, H
-, H
2-, He, He
-, He
2-, He
3- within super-intense laser fields were completed. Also completed were three-dimensional self consistent field calculations to verify the dimensionally scaled quantities. With the aforementioned methods the system's ability to stably bind 'additional' electrons through the development of multiple isolated regions of high potential energy leading to nodes of high electron density is shown. These nodes are spaced far enough from each other to minimized the electronic repulsion of the electrons, while still providing adequate enough attraction so as to bind the excess elections into orbitals. We have found that even with relativistic considerations these species are stably bound within the field. It was also found that performing the dimensional scaling calculations for systems within the confines of laser fields to be a much simpler and more cost-effective method than the supporting D=3 SCF method. The dimensional scaling method is general and can be extended to include relativistic corrections to describe the stability of simple molecular systems in super-intense laser fields.^ Chapter 3, we delineate the model, and aspects therein, of inelastic electron tunneling and map this model to the protein environment. G protein-coupled receptors (GPCRs) constitute a large family of receptors that sense molecules outside of a cell and activate signal transduction pathways inside the cell.…
Advisors/Committee Members: Sabre Kais, David H. Thompson, Adam Wasserman, Lyudmila Slipchenko.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Biophysics; Chemistry
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APA (6th Edition):
Hoehn, R. D. (2014). Quantum mechanics in complex systems. (Doctoral Dissertation). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_dissertations/287
Chicago Manual of Style (16th Edition):
Hoehn, Ross Douglas. “Quantum mechanics in complex systems.” 2014. Doctoral Dissertation, Purdue University. Accessed March 02, 2021.
https://docs.lib.purdue.edu/open_access_dissertations/287.
MLA Handbook (7th Edition):
Hoehn, Ross Douglas. “Quantum mechanics in complex systems.” 2014. Web. 02 Mar 2021.
Vancouver:
Hoehn RD. Quantum mechanics in complex systems. [Internet] [Doctoral dissertation]. Purdue University; 2014. [cited 2021 Mar 02].
Available from: https://docs.lib.purdue.edu/open_access_dissertations/287.
Council of Science Editors:
Hoehn RD. Quantum mechanics in complex systems. [Doctoral Dissertation]. Purdue University; 2014. Available from: https://docs.lib.purdue.edu/open_access_dissertations/287
University of Tennessee – Knoxville
28.
Germann, James Andrew.
Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope.
Degree: 2013, University of Tennessee – Knoxville
URL: https://trace.tennessee.edu/utk_graddiss/2573
► This dissertation presents the development of instrumentation for measuring the position of a single emitter within the sample volume of a confocal fluorescence microscope with…
(more)
▼ This dissertation presents the development of instrumentation for measuring the position of a single emitter within the sample volume of a confocal fluorescence microscope with sub-diffraction limited precision in three dimensions together with applications for determining solution flow and for tracking a fluorescent nanoparticle as it undergoes Brownian diffusion. The localization method is based on comparing photon counts from alternating excitation of the emitter by four laser beams, which are focused at slightly offset positions in a tetrahedral pattern within the confocal volume. Two experimental set-ups are constructed. In the first, the four beams are from a femtosecond laser, which provides two-photon excitation (2PE) of a nanomolar solution of rhodamine B. Time-resolved photon counting into four channels and cross-correlation of the channels yields a set of sixteen curves that vary with the flow of solution through the tetrahedral pattern. Standard fluorescence correlation spectroscopy fitting methods are extended to model solution flow and a Gaussian-Lorentzian beam profile for 2PE. Global fitting of the sixteen curves to extract the flow is studied using data from a collaborator’s computer simulation. The model successfully fits simulated data with flow in one dimension, but accuracy is found to be poor when simultaneously fitting three velocity components. In the second set-up, the four beams are provided by 635-nm fiber-coupled laser diodes. LabVIEW real-time software alternately pulses the diodes, performs time-gated photon counting to estimate the nanoparticle position, and controls a piezo stage to track its motion as it undergoes diffusion. The confocal microscope enables tracking of nanoparticles with diffusivity exceeding 10 µm2 [micron2]s-1, currently limited by the 1.8 ms update interval of the piezo stage, while also providing exceptional sensitivity, with a net fluorescence detection efficiency of about 6%, comparable to that of a highly optimized single-molecule microscope.
Subjects/Keywords: Atomic, Molecular and Optical Physics; Optics
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APA (6th Edition):
Germann, J. A. (2013). Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/2573
Chicago Manual of Style (16th Edition):
Germann, James Andrew. “Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope.” 2013. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed March 02, 2021.
https://trace.tennessee.edu/utk_graddiss/2573.
MLA Handbook (7th Edition):
Germann, James Andrew. “Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope.” 2013. Web. 02 Mar 2021.
Vancouver:
Germann JA. Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2013. [cited 2021 Mar 02].
Available from: https://trace.tennessee.edu/utk_graddiss/2573.
Council of Science Editors:
Germann JA. Tracking Real-Time Nanoparticle Positions and Measuring Three-Dimensional Solution Flow with a Four-Focus Confocal Microscope. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2013. Available from: https://trace.tennessee.edu/utk_graddiss/2573
University of Colorado
29.
Chen, Jwo-Sy.
Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks.
Degree: PhD, Physics, 2017, University of Colorado
URL: https://scholar.colorado.edu/phys_gradetds/218
► The advancement of optical atomic clocks in the past two decades has motivated many potential applications in navigation, communication, and science. Accurate optical clocks that…
(more)
▼ The advancement of
optical atomic clocks in the past two decades has motivated many potential applications in navigation, communication, and science. Accurate
optical clocks that outperform the current cesium time standard also trigger a discussion about a possible redefinition of the SI second. The
27Al
+ quantum logic clocks developed at the National Institute of Standards and Technology (NIST) were the first to achieve the clock fractional frequency uncertainty below 10
-17 in 2010. To date, a few research groups around the world have demonstrated
optical clocks based on various atomic transitions with fractional frequency uncertainty in the 10
-18 range. The accuracy of the previous
27Al
+ clocks was limited by the second order Doppler (time dilation) shift and the blackbody shift. Since 2010, the third
27Al
+ optical clock is being developed at NIST to achieve a higher accuracy. The frequency uncertainties dominant in the previous clocks are controlled and reduced in the current
optical clock. The new design of the ion trap system has reduced significantly both the blackbody radiation shift uncertainty and the time dilation shift uncertainty due to micromotion, while the time dilation shift uncertainty due to the secular motion has been reduced by more than an order of magnitude by operating the
optical clock near the three dimensional zero-point energy. Despite those previously dominant uncertainties, several other systematic effects are being evaluated and some other efforts are being made to achieve a total uncertainty towards 1.0 x 10
-18. In this thesis, I will document the detail of the construction and evaluation of the current
27Al
+ optical clock developed at NIST.
Advisors/Committee Members: David Wineland, David Leibrandt, James Thompson, Murray Holland.
Subjects/Keywords: atomic clock; ion trap; optical clcok; Atomic, Molecular and Optical Physics
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APA ·
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MLA ·
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Export
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APA (6th Edition):
Chen, J. (2017). Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/218
Chicago Manual of Style (16th Edition):
Chen, Jwo-Sy. “Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks.” 2017. Doctoral Dissertation, University of Colorado. Accessed March 02, 2021.
https://scholar.colorado.edu/phys_gradetds/218.
MLA Handbook (7th Edition):
Chen, Jwo-Sy. “Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks.” 2017. Web. 02 Mar 2021.
Vancouver:
Chen J. Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2021 Mar 02].
Available from: https://scholar.colorado.edu/phys_gradetds/218.
Council of Science Editors:
Chen J. Ticking near the Zero-Point Energy: Towards 1 x 10^-18 Accuracy in Al^+ Optical Clocks. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/phys_gradetds/218
Purdue University
30.
Ding, Yu.
Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes.
Degree: PhD, 2014, Purdue University
URL: https://docs.lib.purdue.edu/open_access_dissertations/258
► By implementing a parametric down-conversion process with a strong signal field injection, we demonstrate that frequency down-conversion from pump photons to idler photons can…
(more)
▼ By implementing a parametric down-conversion process with a strong signal field injection, we demonstrate that frequency down-conversion from pump photons to idler photons can be a coherent process. Contrary to a common misconception, we show that the process can be free of quantum noise. With an interference experiment, we demonstrate that coherence is preserved in the conversion process. This technique could lead to a high-fidelity quantum state transfer from a high-frequency photon to a low-frequency photon and connect a missing link in quantum networks. ^ Coherent and efficient nonlinear interaction and frequency conversion are of great interest in many areas of quantum optics. Traditionally, the low efficiency of Raman scattering is improved by a high-finesse
optical resonator or stimulated Raman conversion. It was recently found that the atomic spin wave initially built through electromagnetically induced transparency or a weak Raman process can actively enhance the Raman frequency conversion. An experimental demonstration of an efficient Raman conversion scheme with coherent feedback of both pump and Stokes fields is presented. The temporal profile of the generated Raman pulse shows that the coherence time of the atomic spin wave is ∼1.8 ms. A laser-like power threshold is observed and its low threshold is attributed to the long coherence time of the atomic spin wave. The mechanism of the conversion enhancement process is discussed and the conversion efficiency of a single pass of the beams is compared with that of double passes. Finally, a beat signal is observed between the two Stokes fields and its Fourier transform shows that the frequency difference is caused by the AC Stark effect. ^ Precision phase measurement is traditionally restricted by the standard quantum limit. However, this limit is not as fundamental as the Heisenberg limit and can be circumvented by use of nonclassical quantum states and structure modification of the interferometers. Several examples of nonlinear interferometers are proposed and implemented. The wave propagation equations for the nonlinear interferometers are solved. The interference fringes are measured and compared with that of linear interferometers. The first nonlinear interferometer presented is based on second harmonic generation and degenerate parametric down-conversion. The second nonlinear interferometer is composed of two parametric amplifiers. The idea of nonlinear beam splitters is introduced as an analogy to traditional beam splitters. We show that a nonlinear interferometer can be built alternatively by using only one parametric amplifier. Type II phase-matched crystals can be used to increase the amplification factor. An interferometer based on a Raman amplifier is analyzed for its application to sensitive magnetic field measurement.
Advisors/Committee Members: Zhe-Yu Jeff Ou, Zhe-Yu Jeff Ou, Ricardo Decca, Gautam Vemuri, Marvin D. Kemple, Sergei Savikhin.
Subjects/Keywords: Astrophysics and Astronomy; Atomic, Molecular and Optical Physics; Physics
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ding, Y. (2014). Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes. (Doctoral Dissertation). Purdue University. Retrieved from https://docs.lib.purdue.edu/open_access_dissertations/258
Chicago Manual of Style (16th Edition):
Ding, Yu. “Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes.” 2014. Doctoral Dissertation, Purdue University. Accessed March 02, 2021.
https://docs.lib.purdue.edu/open_access_dissertations/258.
MLA Handbook (7th Edition):
Ding, Yu. “Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes.” 2014. Web. 02 Mar 2021.
Vancouver:
Ding Y. Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes. [Internet] [Doctoral dissertation]. Purdue University; 2014. [cited 2021 Mar 02].
Available from: https://docs.lib.purdue.edu/open_access_dissertations/258.
Council of Science Editors:
Ding Y. Efficient and coherent frequency conversions and nonlinear interference in optical parametric and atomic Raman processes. [Doctoral Dissertation]. Purdue University; 2014. Available from: https://docs.lib.purdue.edu/open_access_dissertations/258
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Open Access Theses and Dissertations