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Limitations On Protecting Information Against Quantum Adversaries, Eneet Kaur 2020 Louisiana State University

Limitations On Protecting Information Against Quantum Adversaries, Eneet Kaur

LSU Doctoral Dissertations

The aim of this thesis is to understand the fundamental limitations on secret key distillation in various settings of quantum key distribution. We first consider quantum steering, which is a resource for one-sided device-independent quantum key distribution. We introduce a conditional mutual information based quantifier for quantum steering, which we call intrinsic steerability. Next, we consider quantum non-locality, which is a resource for device-independent quantum key distribution. In this context, we introduce a quantifier, intrinsic non-locality, which is a monotone in the resource theory of Bell non-locality. Both these quantities are inspired by intrinsic information and squashed entanglement and are …


On Negative Eigenvalues Of The Discrete Schrödinger Operator With Non-Local Potential, Zahriddin Muminov, Shukhrat Lakaev 2020 National University of Uzbekistan

On Negative Eigenvalues Of The Discrete Schrödinger Operator With Non-Local Potential, Zahriddin Muminov, Shukhrat Lakaev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

On the d-dimensional lattice 𝕋d, d= 1, 2 the discrete Schrödinger operator Hλµ with non-local potential constructed via the Dirac delta function and shift operator is considered. The dependency of negative eigenvalues of the operator on the parameters is explicitly derived.


Footprints Of Quantum Pigeons, Gregory Reznick, Shrobona Bagchi, Justin Dressel, Lev Vaidman 2020 Tel-Aviv University

Footprints Of Quantum Pigeons, Gregory Reznick, Shrobona Bagchi, Justin Dressel, Lev Vaidman

Mathematics, Physics, and Computer Science Faculty Articles and Research

We show that in the mathematical framework of the quantum theory, the classical pigeonhole principle can be violated more directly than previously suggested, i.e., in a setting closer to the traditional statement of the principle. We describe how the counterfactual reasoning of the paradox may be operationally grounded in the analysis of the tiny footprints left in the environment by the pigeons. After identifying the drawbacks of recent experiments of the quantum pigeonhole effect, we argue that a definitive experimental violation of the pigeonhole principle is still needed and propose such an implementation using modern quantum computing hardware: a superconducting …


The Breakup Of A Helium Cluster After Removing Attractive Interaction Among A Significant Number Of Atoms In The Cluster, Tao Pang 2020 University of Nevada, Las Vegas

The Breakup Of A Helium Cluster After Removing Attractive Interaction Among A Significant Number Of Atoms In The Cluster, Tao Pang

Physics & Astronomy Faculty Research

The breakup of a quantum liquid droplet is examined through a 4He cluster by removing the attractive tail in the interaction between some of the atoms in the system with the diffusion quantum Monte Carlo simulation. The ground-state energy, kinetic energy, cluster size, and density profile of the cluster are evaluated against the percentage of the atoms without the attractive tail. The condition for the cluster to lose its ability to form a quantum liquid droplet at zero temperature is found and analyzed. The cluster is no longer able to form a quantum liquid droplet when about two-thirds of pairs …


Novel Photon-Detector Models For Enhanced Quantum Information Processing, Elisha Siddiqui 2020 Louisiana State University

Novel Photon-Detector Models For Enhanced Quantum Information Processing, Elisha Siddiqui

LSU Doctoral Dissertations

This work is devoted to the development of novel photon-detector models at room temperature using quantum optics elements. This work comprises of two photon-number-resolving detector (PNRD) models, and the application of PNRD in LIDAR. The first model is based on using a two-mode squeezing device to resolve photon number at room temperature. In this model we study the average intensity-intensity correlations signal at the output of a two-mode squeezing device with |N> and |α> as the two input modes. We show that the input photon-number can be resolved from the average intensity-intensity correlations. In particular, we show jumps in the …


On The Complexity Of Boson Sampling Using Atoms In Optical Lattices, Gopikrishnan Muraleedharan 2020 University of New Mexico - Main Campus

On The Complexity Of Boson Sampling Using Atoms In Optical Lattices, Gopikrishnan Muraleedharan

Physics & Astronomy ETDs

The extended Church-Turing thesis says that any computation that can be done by a physically realizable model of computers can be efficiently computed by the simplest model of classical computer, a Turing machine. Since the introduction of the concept of quantum computers, a central goal has been to find instances where the extended Church- Turing thesis fails. In the current noisy intermediate-scale quantum devices era, one looks for such instances that can be simulated on modest devices of small scale in the presence of noise. In this thesis, we work with one such problem, namely the Boson Sampling problem. We …


Reformulating Bell's Theorem: The Search For A Truly Local Quantum Theory, Mordecai Waegell, Kelvin J. McQueen 2020 Chapman University

Reformulating Bell's Theorem: The Search For A Truly Local Quantum Theory, Mordecai Waegell, Kelvin J. Mcqueen

Philosophy Faculty Articles and Research

The apparent nonlocality of quantum theory has been a persistent concern. Einstein et al. (1935) and Bell (1964) emphasized the apparent nonlocality arising from entanglement correlations. While some interpretations embrace this nonlocality, modern variations of the Everett-inspired many worlds interpretation try to circumvent it. In this paper, we review Bell's “no-go” theorem and explain how it rests on three axioms, local causality, no superdeterminism, and one world. Although Bell is often taken to have shown that local causality is ruled out by the experimentally confirmed entanglement correlations, we make clear that it is the conjunction of the …


Solving Combinatorial Optimization Problems Using The Quantum Approximation Optimization Algorithm, Nicholas J. Guerrero 2020 Air Force Institute of Technology

Solving Combinatorial Optimization Problems Using The Quantum Approximation Optimization Algorithm, Nicholas J. Guerrero

Theses and Dissertations

The Quantum Approximation Optimization Algorithm (QAOA) is one of the most promising applications for noisy intermediate-scale quantum machines due to the low number of qubits required as well as the relatively low gate count. Much work has been done on QAOA regarding algorithm implementation and development; less has been done checking how these algorithms actually perform on a real quantum computer. Using the IBM Q Network, several instances of combinatorial optimization problems (the max cut problem and dominating set problem) were implemented into QAOA and analyzed. It was found that only the smallest toy max cut algorithms performed adequately: those …


Thermodynamic Properties Of Transverse Field Quantum Ising Model Using Tensor Network Formalism, Sin Yang Pang 2020 Universiti Malaya

Thermodynamic Properties Of Transverse Field Quantum Ising Model Using Tensor Network Formalism, Sin Yang Pang

Student Works (2020-2029)

Ising model has been successful in describing ferromagnetism and its phase transition to paramagnet. At the critical point, the free energy density function and its derivatives diverge. Their behaviour near the critical point are described by power-laws with associated critical exponents. In many cases, the critical exponents can be determined from analytic solutions via conventional renormalization groups methods or from Monte Carlo simulations. However, for quantum many-body systems, very few are tractable to analytical solutions. The quantum many-body wavefunction belongs to large dimensional Hilbert space that increases exponentially with system size. If the Hamiltonian is gapped and only local interaction …


Density Functional Theory Study Of Two-Dimensional Boron Nitride Films, Pradip R. Niraula 2020 CUNY Graduate Center

Density Functional Theory Study Of Two-Dimensional Boron Nitride Films, Pradip R. Niraula

Dissertations, Theses, and Capstone Projects

Since graphene was isolated in 2004, the number of two-dimensional (2D) materials and their scientific relevance have grown exponentially. Besides graphene, one of the most important and technolocially promizing 2D materials that has emerged in recent years is hexagonal boron nitride, in its monolayer or multilayer form. In my thesis work, I used density functional theory (DFT) calculations to investigate the properties of boron nitride films. In particular, I first studied the properties (i.e. formation energy, defect states, and structure) of point charged defects in monolayer and bilayer hexagonal boron nitride, and subsequently, I focused on the linear and nonlinear …


Duality In A Model Of Layered Superfluids And Sliding Phases, Steven Vayl 2020 CUNY Graduate Center

Duality In A Model Of Layered Superfluids And Sliding Phases, Steven Vayl

Dissertations, Theses, and Capstone Projects

The intent of my project is to determine if the proposal of sliding phases in XY layered systems has physical ground. It will be done by comparing numerical and analytical results for a layered XY models. Sliding phases were first proposed in the context of DNA complexes and then extended to XY models, 1D coupled wires and superfluid films. The existence of the sliding phase would mean that there is a phase transition from 3D to 2D behavior. Such systems have been studied both in the clean case and with disorder. The idea of the sliding phases is based on …


Computational Modeling Of Charge And Excitation Energy Transfer Dynamics In Complex Environments, Ning Chen 2020 CUNY Graduate Center

Computational Modeling Of Charge And Excitation Energy Transfer Dynamics In Complex Environments, Ning Chen

Dissertations, Theses, and Capstone Projects

This thesis describes computational simulations of charge and exciton dynamics and quantum calculations of organic conjugated oligomers. A comprehensive computational study of charge hopping dynamics was conducted for a model of disordered chain of sites coupled to quantum environments. Time-dependent mean square displacement, diffusion constant, and mobility were calculated by three different computational methods for solving the master equation, which validate the accuracy of calculations. Approximate rate kernels were also tested to understand the effects of approximations in representing quantum environments. In addition to the effects of temperature and disorder, different values of the gradient in the site energy were …


Dual-Axis Solar Tracker, Bryan Kennedy 2020 Central Washington University

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


Luminescence Emission In A Nanocrystal Doped By A Transition Metal Impurity, George Chappell Jr. 2020 Marshall University

Luminescence Emission In A Nanocrystal Doped By A Transition Metal Impurity, George Chappell Jr.

Theses, Dissertations and Capstones

In this thesis we consider the structure of magnetic ion centers with 3d-electrons in quantum dots under the effects of Coulomb and exchange interaction between the 3d-electrons of the impurity centers and the confined electrons (or holes) existing inside the nanocrystals. In particular, we are interested how this interaction changes the photoluminescence properties of those materials. We will make use of representation theory and the symmetry of the crystal structure to find the orthonormal wave functions that make up the wave functions of the outer, 3d-electrons inside our dot. The Coulomb and exchange interaction …


Recent Developments In The Pyscf Program Package, Qiming Sun, Xing Zhang, Samragni Banerjee, Peng Bao, Marc Barbry, Nick S. Blunt, Nikolay A. Bogdanov, George H. Booth, Jia Chen, Zhi-Hao Cui, Janus J. Eriksen, Yang Gao, Sheng Gun, Jan Hermann, Matthew R. Hermes, Kevin Koh, Peter Koval, Susi Lehtola, Zhendong Li, Junzi Liu, Narbe Mardirossian, James D. McClain, Mario Motta, Bastien Mussard, Hung Q. Pham, Artem Pulkin, Wirawan Purwanto, Paul J. Robinson, Enrico Ronca, Elvira R. Sayfutyarova, Maximillian Scheurer, Henry F. Schurkus, James E.T. Smith, Chong Sun, Shi-Ning Sun, Shiv Upadhyay, Lucas K. Wagner, Xiao Wang, Alec White, James Daniel Whitfield, Mark J. Williamson, Sebastian Wouters, Jun Yang, Jason M. Yu, Tianyu Zhu, Timothy C. Berkelbach, Sandeep Sharma, Alexander Yu Sokolov, Garnet Kin-Lic Chan 2020 Old Dominion University

Recent Developments In The Pyscf Program Package, Qiming Sun, Xing Zhang, Samragni Banerjee, Peng Bao, Marc Barbry, Nick S. Blunt, Nikolay A. Bogdanov, George H. Booth, Jia Chen, Zhi-Hao Cui, Janus J. Eriksen, Yang Gao, Sheng Gun, Jan Hermann, Matthew R. Hermes, Kevin Koh, Peter Koval, Susi Lehtola, Zhendong Li, Junzi Liu, Narbe Mardirossian, James D. Mcclain, Mario Motta, Bastien Mussard, Hung Q. Pham, Artem Pulkin, Wirawan Purwanto, Paul J. Robinson, Enrico Ronca, Elvira R. Sayfutyarova, Maximillian Scheurer, Henry F. Schurkus, James E.T. Smith, Chong Sun, Shi-Ning Sun, Shiv Upadhyay, Lucas K. Wagner, Xiao Wang, Alec White, James Daniel Whitfield, Mark J. Williamson, Sebastian Wouters, Jun Yang, Jason M. Yu, Tianyu Zhu, Timothy C. Berkelbach, Sandeep Sharma, Alexander Yu Sokolov, Garnet Kin-Lic Chan

University Administration Publications

PySCF is a Python-based general-purpose electronic structure platform that supports first-principles simulations of molecules and solids as well as accelerates the development of new methodology and complex computational workflows. This paper explains the design and philosophy behind PySCF that enables it to meet these twin objectives. With several case studies, we show how users can easily implement their own methods using PySCF as a development environment. We then summarize the capabilities of PySCF for molecular and solid-state simulations. Finally, we describe the growing ecosystem of projects that use PySCF across the domains of quantum chemistry, materials science, machine learning, and …


Decay And Dissipation: Finding Energy Level Jumps In A Harmonic Oscillator System Using Fortran And Fourier Analysis, Clara Chilton 2020 Claremont Colleges

Decay And Dissipation: Finding Energy Level Jumps In A Harmonic Oscillator System Using Fortran And Fourier Analysis, Clara Chilton

Scripps Senior Theses

In this paper, I will look at a mass-spring system that can be described by a Hamiltonian. In most systems described by a Hamiltonian, the energy levels will be quantized, and the system will be able to jump between them. However, many methods of finding these jumps aren’t well-suited to numerical analysis. I’ll use a Markovian approximation (The Liouville von Neuman Equation), which allows me to use only the last time step to find the current one. Using this, I will analyze the system to find the time evolution of the probability density matrix – whose diagonal shows the probability …


Magnetism In Γ-Fesi2 Nanostructures: A First Principles Study, Sahil Dhoka 2020 Michigan Technological University

Magnetism In Γ-Fesi2 Nanostructures: A First Principles Study, Sahil Dhoka

Dissertations, Master's Theses and Master's Reports

First-principles calculations are performed on γ-FeSi2 nanostructures grown on Si (111) and (001) substrate. An attempt to explain the origin of emergent magnetic properties of the metastable gamma phase of iron di-silicide (γ-FeSi2) is made, which show ferromagnetic behavior on nanoscale, unlike its possible bulk form. Many papers try to explain this magnetism from factors like bulk, epitaxial strain, interface, surface, edges, and corners but doesn’t provide an analytical study for these explanations. Density functional theory is used to analyze the magnetic effects of these factors. The results for the epitaxial structures show no magnetic behavior for …


Modeling Decay Dynamics In Systems Of Nanoparticles, Jacob Smith 2020 University of Alabama in Huntsville

Modeling Decay Dynamics In Systems Of Nanoparticles, Jacob Smith

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.


Resource Efficient Design Of Quantum Circuits For Cryptanalysis And Scientific Computing Applications, Edgard Munoz-Coreas 2020 University of Kentucky

Resource Efficient Design Of Quantum Circuits For Cryptanalysis And Scientific Computing Applications, Edgard Munoz-Coreas

Theses and Dissertations--Electrical and Computer Engineering

Quantum computers offer the potential to extend our abilities to tackle computational problems in fields such as number theory, encryption, search and scientific computation. Up to a superpolynomial speedup has been reported for quantum algorithms in these areas. Motivated by the promise of faster computations, the development of quantum machines has caught the attention of both academics and industry researchers. Quantum machines are now at sizes where implementations of quantum algorithms or their components are now becoming possible. In order to implement quantum algorithms on quantum machines, resource efficient circuits and functional blocks must be designed. In this work, we …


Acoustics To Quantum Materials: A Centennial History Of The Department Of Physics, University Of Arkansas, Rajendra Gupta, Paul C. Sharrah 2020 University of Arkansas, Fayetteville

Acoustics To Quantum Materials: A Centennial History Of The Department Of Physics, University Of Arkansas, Rajendra Gupta, Paul C. Sharrah

Physics Faculty Publications and Presentations

The department of physics at the University of Arkansas was established in the 1907-08 academic year, although physics was taught from the very start of the University in 1872. The department celebrated its centennial in 2007-2008. Acoustics to Quantum Materials is a centennial history of the department covering the period 1907-08 to 2007-08. While the emphasis is on this period, instruction of physics over the period 1872-1907 is covered in two prologues, and the period 2009-18 is briefly covered in an epilogue. The first research laboratory to be established was in the area of acoustics. Subsequently, the department’s faculty have …


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