Single-Stage Few-Cycle Pulse Amplification, 2024 Manipal Institute of Technology, Manipal University

#### Single-Stage Few-Cycle Pulse Amplification, Sagnik Ghosh, Nathan G. Drouillard, Tj Hammond

*Physics Publications*

Kerr instability can be exploited to amplify visible, near-infrared, and midinfrared ultrashort pulses. We use the results of Kerr instability amplification theory to inform our simulations amplifying few-cycle pulses. We show that the amplification angle dependence is simplified to the phase-matching condition of four-wave mixing when the intense pump is considered. Seeding with few-cycle pulses near the pump leads to broadband amplification without spatial chirp, while longer pulses undergo compression through amplification. Pumping in the midinfrared leads to multioctave spanning amplified pulses with single-cycle duration not previously predicted. We discuss limitations of the amplification process and optimizing pump and seed …

Theory Of Ultrafast Spin Crossover In Divalent Iron Systems, 2024 Northern Illinois University

#### Theory Of Ultrafast Spin Crossover In Divalent Iron Systems, William Baker

*Graduate Research Theses & Dissertations*

A theory to account for the ultrafast, i.e. femtosecond timescale, singlet to quintet spin crossover in divalent iron molecules is developed. The model considers an iron cluster with ligands extending in all 6 cardinal directions initially at rest in a low spin singlet ground state. An optical excitation excites an electron from the d orbitals to the ligands, changing the system from the metal centered (MC) singlet state to the metal to ligand charge transfer (MLCT) singlet state. Experimentally, it is known that the system eventually relaxes into the quintet MC state, but there are no satisfactory explanations that model …

Solutions To The Kaluza-Klein Field Equations, 2024 Minnesota State University, Mankato

#### Solutions To The Kaluza-Klein Field Equations, Abel Eshete

*All Graduate Theses, Dissertations, and Other Capstone Projects*

This Alternate Paper Plan explores Kaluza-Klein theory, a multidimensional framework designed to unify Einstein’s gravitational field theory and Maxwell’s electromagnetic field theory. The objectives of this research can be summarized in two key areas: The first objective is to present a comprehensive introduction to the compactified Kaluza-Klein theory. The second aim involves the application of differential geometry, specifically E ́lie Cartan’s tetrad formalism, to derive exact solutions in two distinct scenarios: a. A Levi-Civita spacetime, b. A general spherical system. Furthermore, Lagrangian and Hamiltonian formalism are utilized to define stability conditions and describe gravitational lensing and Precession of Perihelion within …

Existence Of Well-Defined Pointer Observable Selects Tensor Product Factorizations Of Quantum Systems, 2024 Claremont Colleges

#### Existence Of Well-Defined Pointer Observable Selects Tensor Product Factorizations Of Quantum Systems, Brian Lee

*CMC Senior Theses*

In the decoherence account of quantum mechanics, a choice of particular tensor product structure (a particular partition of system into subsystems) is assumed. We explore whether it is possible to relax this arbitrary choice by requiring that a valid tensor product structure admits a quasi-classical description. Such tensor product structures are said to be quasi-classical or decoherence-selected tensor product structures. This project generalizes a 2-qubit quasi-classical tensor product structure selection algorithm to an n-qubit selection algorithm, which allows us to, for the first time, consider the relationship between decoherence-selected tensor product structures and locality-selected tensor product structures. To generalize the …

Higher-Derivative Quantum Field Theory And Its Implications For Hawking Radiation And Nonlocality, 2024 University of Texas at Arlington

#### Higher-Derivative Quantum Field Theory And Its Implications For Hawking Radiation And Nonlocality, Gordon Kanan

*Physics Dissertations*

One of the fundamental equations of quantum field theory is the Klein-Gordon equation which can be constructed using irreducible representations of the Poincar ́e group and describes the dynamics of spin-0 matter. The higher derivative Klein- Gordon equations are also constructed using irreducible representations of the Poincar ́e group and are, thus, invariant under operations of this group. These higher derivative Klein-Gordon equations can be placed into two series depending on the power of the derivative, one for odd powers of the derivative and one for even powers, whose solu- tions yield timelike and spacelike fields. Applying these higher derivative …

Double Distributions And Pseudodistributions, 2024 Old Dominion University

#### Double Distributions And Pseudodistributions, A. V. Radyushkin

*Physics Faculty Publications*

We describe the approach to lattice extraction of generalized parton distributions (GPDs) that is based on the use of the double distribution (DD) formalism within the pseudodistribution framework. The advantage of using DDs is that GPDs obtained in this way have the mandatory polynomiality property, a nontrivial correlation between 𝓍 and ξ dependences of GPDs. Another advantage of using DDs is that the D-term appears as an independent entity in the DD formalism rather than a part of GPDs H and E. We relate the ξ dependence of GPDs to the width of the α profiles of the corresponding DDs …

Gluon Helicity From Global Analysis Of Experimental Data And Lattice Qcd Ioffe Time Distributions, 2024 Jefferson Lab

#### Gluon Helicity From Global Analysis Of Experimental Data And Lattice Qcd Ioffe Time Distributions, J. Karpie, R. M. Whitehill, W. Melnitchouk, C. Monahan, K. Orginos, J.-W. Qui, D. G. Richards, N. Sato, S. Zafeiropoulos, Jefferson Lab Angular Momentum And Hadstruc Collaboration

*Physics Faculty Publications*

We perform a new global analysis of spin-dependent parton distribution functions with the inclusion of Ioffe time pseudodistributions computed in lattice QCD (LQCD), which are directly sensitive to the gluon helicity distribution, **Δ g**. These lattice data have an analogous relationship to parton distributions as do experimental cross sections, and can be readily included in global analyses. We focus in particular on the constraining capability of current LQCD data on the sign of

**Δ**at intermediate parton momentum fractions

*g**x*, which was recently brought into question by analysis of data in the absence of parton positivity constraints. …

Evolution Of Efimov States, 2024 University of Washington

#### Evolution Of Efimov States, Sebastian M. Dawid, Md Habib E. Islam, Raúl A. Briceño, Andrew W. Jackura

*Physics Faculty Publications*

The Efimov phenomenon manifests itself as an emergent discrete scaling symmetry in the quantum three-body problem. In the unitarity limit, it leads to an infinite tower of three-body bound states with energies forming a geometric sequence. In this work, we study the evolution of these so-called Efimov states using relativistic scattering theory. We identify them as poles of the three-particle **𝑆** matrix in the complex energy plane, and we study how they transform from virtual states through bound states to resonances when we change the interaction strength. We dial the scattering parameters toward the unitarity limit and observe the emergence …

𝑋𝑌𝑍 Spectroscopy At Electron-Hadron Facilities. Iii. Semi-Inclusive Processes With Vector Exchange, 2024 Universität Bonn

#### 𝑋𝑌𝑍 Spectroscopy At Electron-Hadron Facilities. Iii. Semi-Inclusive Processes With Vector Exchange, D. Winney, A. Pilloni, R. J. Perry, Ł. Bibrzycki, C. Fernández-Ramírez, N. Hammoud, V. Mathieu, G. Montaña, A. Rodas, V. Shastry, W. A. Smith, A. P. Szczepaniak

*Physics Faculty Publications*

Inclusive production processes will be important for the first observations of 𝑋𝑌𝑍 states at new generation electron-hadron colliders, as they generally benefit from larger cross sections than their exclusive counterparts. We make predictions of semi-inclusive photoproduction of the 𝜒_{𝑐1}(1𝑃) and 𝑋(3872), whose peripheral production is assumed to be dominated by vector exchanges. We validate the applicability of vector meson dominance in the axial-vector charmonium sector and calculate production rates at center-of-mass energies relevant for future experimental facilities. We find the semi-inclusive cross sections near the threshold to be enhanced by a factor of ∼2–3 compared to the exclusive …

The Present And Future Of Qcd, 2024 Thomas Jefferson National Accelerator Facility

#### The Present And Future Of Qcd, P. Achenbach, D. Adhikari, A. Afanasev, F. Afzal, C. A. Aidala, A. Al-Bataineh, D. K. Almaalol, M. Amaryan, D. Androić, W. R. Armstrong, M. Arratia, J. Arrington, A. Asaturyan, E. C. Aschenauer, H. Atac, H. Avakian, T. Averett, C. Ayerbe Gayoso, X. Bai, M. Zurek, Et. Al.

*Physics Faculty Publications*

This White Paper presents an overview of the current status and future perspective of QCD research, based on the community inputs and scientific conclusions from the 2022 Hot and Cold QCD Town Meeting. We present the progress made in the last decade toward a deep understanding of both the fundamental structure of the sub-atomic matter of nucleon and nucleus in cold QCD, and the hot QCD matter in heavy ion collisions. We identify key questions of QCD research and plausible paths to obtaining answers to those questions in the near future, hence defining priorities of our research over the coming …

A Formalism For Extracting Track Functions From Jet Measurements, 2024 Massachusetts Institute of Technology

#### A Formalism For Extracting Track Functions From Jet Measurements, Kyle Lee, Ian Moult, Felix Ringer, Wouter J. Waalewijn

*Physics Faculty Publications*

The continued success of the jet substructure program will require widespread use of tracking information to enable increasingly precise measurements of a broader class of observables. The recent reformulation of jet substructure in terms of energy correlators has simplified the incorporation of universal non-perturbative matrix elements, so called “track functions”, in jet substructure calculations. These advances make it timely to understand how these universal non-perturbative functions can be extracted from hadron collider data, which is complicated by the use jet algorithms. In this paper we introduce a new class of jet functions, which we call (semi-inclusive) track jet functions, which …

Quantum Logic Control And Precision Measurements Of Molecular Ions In A Ring Trap: An Approach For Testing Fundamental Symmetries, 2024 University of Nevada, Las Vegas

#### Quantum Logic Control And Precision Measurements Of Molecular Ions In A Ring Trap: An Approach For Testing Fundamental Symmetries, Yan Zhou, Joshua O. Island, Matt Grau

*Physics Faculty Publications*

This paper presents an experimental platform designed to facilitate quantum logic control of polar molecular ions in a segmented ring ion trap, paving the way for precision measurements. This approach focuses on achieving near-unity state preparation and detection, as well as long spin-precession coherence. A distinctive aspect lies in separating state preparation and detection conducted in a static frame from parity-selective spin precession in a rotating frame. Moreover, the method is designed to support spatially and temporally coincident measurements on multiple ions prepared in states with different sensitivity to the new physics of interest. This provides powerful techniques to probe …

Continuous-Variable Quantum Computation Of The O(3) Model In 1+1 Dimensions, 2024 Thomas Jefferson National Accelerator Facility

#### Continuous-Variable Quantum Computation Of The O(3) Model In 1+1 Dimensions, Raghav G. Jha, Felix Ringer, George Siopsis, Shane Thompson

*Physics Faculty Publications*

We formulate the O(3) nonlinear sigma model in 1+1 dimensions as a limit of a three-component scalar field theory restricted to the unit sphere in the large squeezing limit. This allows us to describe the model in terms of the continuous-variable (CV) approach to quantum computing. We construct the ground state and excited states using the coupled-cluster *Ansatz* and find excellent agreement with the exact diagonalization results for a small number of lattice sites. We then present the simulation protocol for the time evolution of the model using CV gates and obtain numerical results using a photonic quantum simulator. We …

Complexity, Entanglement And Codes In Quantum Field Theory, 2024 University of Kentucky

#### Complexity, Entanglement And Codes In Quantum Field Theory, Nikolaos Angelinos

*Theses and Dissertations--Physics and Astronomy*

In recent decades many deep connections between quantum information theory and quantum field theory have been unearthed. In this dissertation we study topics in high-energy physics through the lens of quantum information: 1) We develop connections between error-correcting codes and Narain conformal field theories. 2) We study the entanglement entropy of one-dimensional fermionic chains with long-range interactions. 3) We study the temperature dependence of Lanczos coefficients and Krylov complexity.

Modeling Lithographic Quantum Dots And Donors For Quantum Computation And Simulation, 2023 University of New Mexico

#### Modeling Lithographic Quantum Dots And Donors For Quantum Computation And Simulation, Mitchell Ian Brickson

*Physics & Astronomy ETDs*

Our first focus is on few-hole quantum dots in germanium. We use discontinous Galerkin methods to discretize and solve the equations of a highly detailed k·p model that describes these systems, enabling a better understanding of experimental magnetospectroscopy results. We confirm the expected anisotropy of single-hole g-factors and describe mechanisms by which different orbital states have different g-factors. Building on this, we show that the g-factors in Ge holes are suciently sensitive to details of the device electrostatics that magnetospectroscopy data can be used to make a prediction of the underlying confinement potential. The second focus is on designing quantum …

Quantum Computers For Nuclear Physics, 2023 Mississippi State University

#### Quantum Computers For Nuclear Physics, Muhammad F. Yusf

*Theses and Dissertations*

We explore the paradigm shift in quantum computing and quantum information science, emphasizing the synergy between hardware advancements and algorithm development. Only now have the recent advances in quantum computing hardware, despite a century of quantum mechanics, unveiled untapped potential, requiring innovative algorithms for full utilization. Project 1 addresses quantum applications in radiative reactions, overcoming challenges in many-fermion physics due to imaginary time evolution, stochastic methods like Monte Carlo simulations, and the associated sign problem. The methodology introduces the Electromagnetic Transition System and a general two-level system for computing radiative capture reactions. Project 2 utilizes Variational Quantum Eigensolver (VQE) to …

High-Performance Computing In Covariant Loop Quantum Gravity, 2023 The University of Western Ontario

#### High-Performance Computing In Covariant Loop Quantum Gravity, Pietropaolo Frisoni

*Electronic Thesis and Dissertation Repository*

This Ph.D. thesis presents a compilation of the scientific papers I published over the last three years during my Ph.D. in loop quantum gravity (LQG). First, we comprehensively introduce spinfoam calculations with a practical pedagogical paper. We highlight LQG's unique features and mathematical formalism and emphasize the computational complexities associated with its calculations. The subsequent articles delve into specific aspects of employing high-performance computing (HPC) in LQG research. We discuss the results obtained by applying numerical methods to studying spinfoams' infrared divergences, or ``bubbles''. This research direction is crucial to define the continuum limit of LQG properly. We investigate the …

Formulation Of Causality-Preserving Quantum Time Of Arrival Theory, 2023 National Institute of Physics, College of Science, University of the Philippines, Diliman

#### Formulation Of Causality-Preserving Quantum Time Of Arrival Theory, Denny Lane B. Sombillo, Neris I. Sombillo

*Physics Faculty Publications*

We revisit the quantum correction to the classical time of arrival to address the unphysical instantaneous arrival in the limit of zero initial momentum. In this study, we show that the vanishing of arrival time is due to the contamination of the causality-violating component of the initial wave packet. Motivated by this observation, we propose to update the temporal collapse mechanism in Galapon (2009) [18] to incorporate the removal of causality-violating spectra of the arrival time operator. We found that the quantum correction to the classical arrival time is still observed. Thus, our analysis validates that the correction is an …

Sensitive Capacitance Measurements Of The Quantum Hall Effect In Graphene, 2023 University of Nevada, Las Vegas

#### Sensitive Capacitance Measurements Of The Quantum Hall Effect In Graphene, Vergil Schreiber, Justin Alvarez, Joshua Island

*Undergraduate Research Symposium Podium Presentations*

Research on how electrons respond to confinement holds potential for breakthroughs in quantum computing and more energy efficient electronics. In intense magnetic fields and near-zero temperatures, electrons in confined to 2D display unique quantum behaviors. These conditions quantize electron motion into circular orbits, resulting in discrete Landau energy levels.

Generative Adversarial Game With Tailored Quantum Feature Maps For Enhanced Classification, 2023 University of Tennessee, Knoxville

#### Generative Adversarial Game With Tailored Quantum Feature Maps For Enhanced Classification, Anais Sandra Nguemto Guiawa

*Doctoral Dissertations*

In the burgeoning field of quantum machine learning, the fusion of quantum computing and machine learning methodologies has sparked immense interest, particularly with the emergence of noisy intermediate-scale quantum (NISQ) devices. These devices hold the promise of achieving quantum advantage, but they grapple with limitations like constrained qubit counts, limited connectivity, operational noise, and a restricted set of operations. These challenges necessitate a strategic and deliberate approach to crafting effective quantum machine learning algorithms.

This dissertation revolves around an exploration of these challenges, presenting innovative strategies that tailor quantum algorithms and processes to seamlessly integrate with commercial quantum platforms. A …