Generating Entanglement With The Dynamical Lamb Effect, 2020 The Graduate Center, City University of New York

#### Generating Entanglement With The Dynamical Lamb Effect, Mirko Amico

*All Dissertations, Theses, and Capstone Projects*

According to quantum field theory, the vacuum is filled with virtual particles which can be turned into real ones under the influence of external perturbations. Phenomena of this kind are commonly referred to as quantum vacuum phenomena. Several quantum vacuum phenomena related to the peculiar nature of the quantum vacuum have been predicted, some of which, such as the Lamb shift and the Casimir effect, have been experimentally found. Other examples of quantum vacuum phenomena include the Unruh effect, the dynamical Casimir effect and the dynamical Lamb effect. The dynamical Lamb effect was first predicted by considering the situation of ...

Small-X Qcd Calculations With A Biased Ensemble, 2020 The Graduate Center, City University of New York

#### Small-X Qcd Calculations With A Biased Ensemble, Gary Kapilevich

*All Dissertations, Theses, and Capstone Projects*

In this dissertation, I will argue that we can study functional fluctuations in unintegrated gluon distributions, in the MV model as well as JIMWLK, using reweighting techniques, which will allow me to calculate QCD observables with "biased ensembles". This technique will enable me to study rare functional configurations of the gluon distributions, that might have been selected for in, for example, the centrality criteria used by the ATLAS and ALICE collaborations. After a review of these techniques, as well as a review of QCD physics at high energy in general, I will use biased ensembles to compute observables in two ...

At The Interface Of Algebra And Statistics, 2020 The Graduate Center, City University of New York

#### At The Interface Of Algebra And Statistics, Tai-Danae Bradley

*All Dissertations, Theses, and Capstone Projects*

This thesis takes inspiration from quantum physics to investigate mathematical structure that lies at the interface of algebra and statistics. The starting point is a passage from classical probability theory to quantum probability theory. The quantum version of a probability distribution is a density operator, the quantum version of marginalizing is an operation called the partial trace, and the quantum version of a marginal probability distribution is a reduced density operator. Every joint probability distribution on a finite set can be modeled as a rank one density operator. By applying the partial trace, we obtain reduced density operators whose diagonals ...

Density Functional Theory Calculations Of Al Doped Hafnia For Different Crystal Symmetry Configurations, 2020 Seton Hall University

#### Density Functional Theory Calculations Of Al Doped Hafnia For Different Crystal Symmetry Configurations, Joshua Steier

*Seton Hall University Dissertations and Theses (ETDs)*

Dogan et al.[1], investigated the causes of ferroelectricity in doped hafnia using ab initio methods. Similarly, we investigated the stability of Al doped hafnia using quantum mechanical methods.

There are many different phases of Hafnia: monoclinic, tetragonal, cubic and orthorhombic. Starting with the monoclinic phase of Hafnia, Hafnia undergoes phase transitions which result in different space groups. The temperature at which the tetragonal phase is induced is 2000 K and cubic phase is induced at 2900 K[1]. Different dielectric constants vary from phase to phase. The average dielectric constants are highest for the cubic and tetragonal phases. In ...

On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, 2020 Chapman University

#### On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva

*Computational and Data Sciences (PhD) Dissertations*

This is a dissertation in two parts. In the first one, the Aharonov-Bohm effect is investigated. It is shown that solenoids (or flux lines) can be seen as barriers for quantum charges. In particular, a charge can be trapped in a sector of a long cavity by two flux lines. Also, grids of flux lines can approximate the force associated with continuous two-dimensional distributions of magnetic fields. More, if it is assumed that the lines can be as close to each other as desirable, it is explained how the classical magnetic force can emerge from the Aharonov-Bohm effect. Continuing, the ...

Conservation Of Orbital Angular Momentum In Degenerate Four-Wave Mixing Via Rubidium Vapor, 2020 William & Mary

#### Conservation Of Orbital Angular Momentum In Degenerate Four-Wave Mixing Via Rubidium Vapor, Kangning Yang

*Undergraduate Honors Theses*

We present an experimental platform which can generate quantum-correlated beams with Orbital Angular Momentum (OAM) via degenerate Four-Wave Mixing (FWM) in Rubidium vapor. We further investigated the conservation of OAM before and after FWM by performing LG mode decomposition using interferometer. To compare our experimental result with theoretical prediction, we simulated a simplified version of our set up. Moreover, we used this toy model to study the conservation of radial and angular intensity profile through changing parameters limited by our set up. In general, we found that FWM preserves most information consisted in OAM, but has a rather loose control ...

Studies In Seop Hyperpolarized 3he: Measuring Ko And The Spatial Dependence Of Alkali Polarization, 2020 William & Mary

#### Studies In Seop Hyperpolarized 3he: Measuring Ko And The Spatial Dependence Of Alkali Polarization, Michael Cairo

*Undergraduate Honors Theses*

^{3}He is an isotope of helium whose nucleus is composed of two protons and one neutron. The proportion of atoms whose spins are pointed along the same direction in a volume of ^{3}He gas is known as the polarization. This study entails two experiments in the field of ^{3}He polarimetry concerned with measuring the polarization of a ^{3}He cell and reducing the uncertainty associated with it. ^{3}He cells are full of gaseous ^{3}He, along with alkali metal vapors, K and Rb in our case. The polarization of a ^{3}He cell can be measured ...

Quantum Computing And Quantum Algorithms, 2020 Liberty University

#### Quantum Computing And Quantum Algorithms, Daniel Serban

*Senior Honors Theses*

The field of quantum computing and quantum algorithms is studied from the ground up. Qubits and their quantum-mechanical properties are discussed, followed by how they are transformed by quantum gates. From there, quantum algorithms are explored as well as the use of high-level quantum programming languages to implement them. One quantum algorithm is selected to be implemented in the Qiskit quantum programming language. The validity and success of the resulting computation is proven with matrix multiplication of the qubits and quantum gates involved.

Magnetic Forces In The Absence Of A Classical Magnetic Field, 2020 Chapman University

#### Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell

*Mathematics, Physics, and Computer Science Faculty Articles and Research*

It is shown that, in some cases, the effect of discrete distributions of flux lines in quantum mechanics can be associated with the effect of continuous distributions of magnetic fields with special symmetries. In particular, flux lines with an arbitrary value of magnetic flux can be used to create energetic barriers, which can be used to confine quantum systems in specially designed configurations. This generalizes a previous work where such energy barriers arose from flux lines with half-integer fluxons. Furthermore, it is shown how the Landau levels can be obtained from a two-dimensional grid of flux lines. These results suggest ...

Limitations On Protecting Information Against Quantum Adversaries, 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, 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 𝕋^{d}, *d*= 1, 2 the discrete Schrödinger operator *H*_{λµ} 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.

On The Number Of The Discrete Spectrum Of Two-Particle Discrete Schröodinger Operators, 2020 National University of Uzbekistan

#### On The Number Of The Discrete Spectrum Of Two-Particle Discrete Schröodinger Operators, Zahriddin Muminov, Utkir Kuljanov, Shukhrat Alladustov

*Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences*

We consider a family of discrete Schrö dinger operators *h ^{d}(k)*, where

*k*is the two-particle quasi-momentum varying in 𝕋

^{d}=(−π,π]

*, associated to a system of two-particles on the*

^{d}*d*- dimensional lattice ℤ

^{d},

*d*>1. The CwikelLieb-Rozenblum (CLR)-type estimates are written for

*h*when the Fermi surface

^{d}(k)*E*(𝔢

_{k}^{-1}_{m}(k)) of the associated dispersion relation is a one point set at em(k), the bottom of the essential spectrum. Moreover, when the Fermi surface

*E*(𝔢

_{k}^{-1}_{m}(k)) is of dimension

*d−1*or

*d−2*, we ...

Atomic Magnetometry For The Detection Of Cardio-Magnetic Fields, 2020 William & Mary

#### Atomic Magnetometry For The Detection Of Cardio-Magnetic Fields, Alexander Fay

*Undergraduate Honors Theses*

We demonstrate a method of measuring small constant gradients on top of a large constant background magnetic field using Electromagnetically Induced Transparency (EIT). The Earth provides a constant magnetic field of 25-50 μT, and as such, measuring much smaller magnetic fields as well as smaller gradients presents a challenge often requiring special shielding. We show that by making use of common mode noise subtraction from a dual rail setup, our measurement is insensitive to these large fields, and in theory our method does not require shielding. Our dual rail setup allows us to measure small magnetic field gradients by utilizing ...

Novel Photon-Detector Models For Enhanced Quantum Information Processing, 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 ...

Solving Combinatorial Optimization Problems Using The Quantum Approximation Optimization Algorithm, 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 ...

Density Functional Theory Study Of Two-Dimensional Boron Nitride Films, 2020 The Graduate Center, City University of New York

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

*All 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 ...

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

Optical-Depth Scaling Of Light Scattering From A Dense And Cold Atomic 87Rb Gas, 2020 Old Dominion University

#### Optical-Depth Scaling Of Light Scattering From A Dense And Cold Atomic 87Rb Gas, K. J. Kemp, S. J. Roof, M. D. Havey, I. M. Sokolov, D. V. Kupriyanov, W. Guerin

*Physics Faculty Publications*

We report investigation of near-resonance light scattering from a cold and dense atomic gas of ^{87}Rb atoms. Measurements are made for probe frequencies tuned near the F=2→ F'=3 nearly closed hyperfine transition, with particular attention paid to the dependence of the scattered light intensity on detuning from resonance, the number of atoms in the sample, and atomic sample size. We find that, over a wide range of experimental variables, the optical depth of the atomic sample serves as an effective single scaling parameter which describes well all the experimental data.

Neutron Valence Structure From Nuclear Deep Inelastic Scattering, 2020 Old Dominion University

#### Neutron Valence Structure From Nuclear Deep Inelastic Scattering, E. P. Segarra, A. Schmidt, T. Kutz, D. W. Higinbotham, E. Piasetzky, M. Strikman, L. B. Weinstein, O. Hen

*Physics Faculty Publications*

Mechanisms of spin-flavor SU(6) symmetry breaking in quantum chromodynamics (QCD) are studied via an extraction of the free neutron structure function from a global analysis of deep inelastic scattering (DIS) data on the proton and on nuclei from A = 2 (deuterium) to 208 (lead). Modification of the structure function of nucleons bound in atomic nuclei (known as the EMC effect) are consistently accounted for within the framework of a universal modification of nucleons in short-range correlated (SRC) pairs. Our extracted neutron-to-proton structure function ratio F^{n}_{2}/F^{p}_{2} becomes constant for *x*_{B }≥ 0.6, equaling 0 ...

Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, 2019 Chapman University

#### Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, Razieh Mohseninia, José Raúl González Alonso, Justin Dressel

*Mathematics, Physics, and Computer Science Faculty Articles and Research*

Out-of-time-ordered correlators (OTOCs) have been proposed as a tool to witness quantum information scrambling in many-body system dynamics. These correlators can be understood as averages over nonclassical multitime quasiprobability distributions (QPDs). These QPDs have more information and their nonclassical features witness quantum information scrambling in a more nuanced way. However, their high dimensionality and nonclassicality make QPDs challenging to measure experimentally. We focus on the topical case of a many-qubit system and show how to obtain such a QPD in the laboratory using circuits with three and four sequential measurements. Averaging distinct values over the same measured distribution reveals either ...