Physics Commons^™

Quantics Tensor Trains: The Study Of A Continuous Lattice Model And Beyond, Aleix Bou Comas

Dissertations, Theses, and Capstone Projects

This four-chapter dissertation studies the efficient discretization of continuous variable functions with tensor train representation. The first chapter describes all the methodology used to discretize functions and store them efficiently. In this section, the algorithm tensor renormalization group is explained for self-containment purposes. The second chapter centers around the XY model. Quantics tensor trains are used to describe the transfer matrix of the model and compute one and two-dimensional quantities. The one dimensional magnitudes are compared to analytical results with an agreement close to machine precision. As for two dimensions, the analytical results cannot be computed. However, the critical temperature …

A Causal Inference Approach For Spike Train Interactions, Zach Saccomano

Dissertations, Theses, and Capstone Projects

Since the 1960s, neuroscientists have worked on the problem of estimating synaptic properties, such as connectivity and strength, from simultaneously recorded spike trains. Recent years have seen renewed interest in the problem coinciding with rapid advances in experimental technologies, including an approximate exponential increase in the number of neurons that can be recorded in parallel and perturbation techniques such as optogenetics that can be used to calibrate and validate causal hypotheses about functional connectivity. This thesis presents a mathematical examination of synaptic inference from two perspectives: (1) using in vivo data and biophysical models, we ask in what cases the …

Exciton Dynamics, Interaction, And Transport In Monolayers Of Transition Metal Dichalcogenides, Saroj Chand

Dissertations, Theses, and Capstone Projects

Monolayers Transition metal dichalcogenides (TMDs) have attracted much attention in recent years due to their promising optical and electronic properties for applications in optoelectronic devices. The rich multivalley band structure and sizable spin-orbit coupling in monolayer TMDs result in several optically bright and dark excitonic states with different spin and valley configurations. In the proposed works, we have developed experimental techniques and theoretical models to study the dynamics, interactions, and transport of both dark and bright excitons.

In W-based monolayers of TMDs, the momentum dark exciton cannot typically recombine optically, but they represent the lowest excitonic state of the system …

Physics 100 Level Laboratory Data Collection Tables, Kalani Hettiarachchilage

Open Educational Resources

The physics 100-level laboratory part demonstrates and applies the material learned from related classes. This document shows guidelines for collecting data and analyzing them by using Microsoft Excel. Laboratory components of PHY 114/ PHY 206/SLS 261 (Introduction to Physics and Nature of Physical Processes), PHY116/PHY 121 (Physics I and General Physics I), and PHY 156/PHY 161 (Physics II and General Physics II) at College of Staten Island are in-person mandatory sessions for students and it is required to pass to receive a passing grade for that class. This part is taught by different instructors. Although everyone is supposed to follow …

Physics Ii, Kalani Hettiarachchilage

Open Educational Resources

Physics II, class code PHY 156 at College of Staten Island is the second part of two two-semester algebra-based introductory physics courses. This course overlaps of the following topics laws of electricity, magnetism, optics, and modern physics. The important laws of physics in these areas and problem-solving are emphasized. Problem solving is an integral part of the course, all contents are designed to think critically, analytically, and logically. Conceptual understanding is reinforced using interactive computer-based techniques, demonstrations, problem-solving strategies, and laboratory experiences. In this document, all the class materials including lectures, worksheets, homework, group work assignments, quizzes, and conceptual Slido …

Creative Physics Syllabus For Online Class, Kalani Hettiarachchilage

Open Educational Resources

Creative Physics syllabus for all information and guidelines will be a big help for students to know about the class structure, expectations, submission, personalized class materials, class ethics, and requirements in one place. This detailed syllabus will be a very effective way of expressing the information to the class. Creating a detailed syllabus and engaging activity of in the learning management system such as syllabus review activity will help students to navigate through important items on the syllabus.

Physics I, Kalani Hettiarachchilage

Open Educational Resources

Physics I, class code PHY 116 at College of Staten Island is the first part of a two-semester algebra-based introductory physics course. This course overlaps many topics in the laws of classical mechanics, fluid dynamics, thermodynamics, wave motion, and sound. The important laws of physics in these areas and problem-solving are emphasized. Problem solving is an integral part of the course, all contents are designed to think critically, analytically, and logically. Conceptual understanding is reinforced using interactive computer-based techniques, demonstrations, problem-solving strategies, and laboratory experiences. In this document, all the class materials including lectures, worksheets, homework and group work assignments, …

Introduction To Physics, Kalani Hetti

Open Educational Resources

Introduction to physics, class code PHY 114 at college of Staten Island covers general physics concepts by using very simple algebraic calculations. Topics may include scientific measurements, significant figures, estimation, units, linear and rotational motion, vectors, forces, energy, momentum, collision, impulse, projectile motion, circular motion, thermodynamics, oscillating waves, electricity and magnetism, properties of lights, reflection, refraction, atomic nuclei, and radioactivity. This course is designed to teach general concepts and laws of physics to everyday life enforcing student’s critical thinking, logical patterns, organization, and everyday life applications. In this document, all the class materials including lectures, worksheets, homework assignments, quizzes, and …

Nonlinear Processes In Room Temperature Exciton-Polaritons, Prathmesh Deshmukh

Dissertations, Theses, and Capstone Projects

Strong light-matter coupling in solid state systems is an intriguing process that allows one to exploit the advantages of both light and matter. In this context, microcavities have become essential platforms for studying the strong coupling regime, where hybrid light-matter states known as exciton-polaritons form, leading to enhanced light matter interaction, modified material properties, and novel quantum phenomena. In this thesis, we explore the phenomenology of exciton-polaritons in strained TMD microcavities, 2D perovskites, fluorescent proteins and organic dyes encompassing thermalization, polariton lasing, and the observation of nonlinear effects.

Transition metal dichalcogenides (TMDs) have emerged as a remarkable class of two- …

The Role Of Nuclear Quantum Effects In Supercooled Water And Amorphous Ice, Ali H. Eltareb

Dissertations, Theses, and Capstone Projects

Water is one of the most important substances on Earth and plays a fundamental role in numerous scientific and engineering applications. Interestingly, water behaves much differently than other liquids. For example, water shows an anomalous density maximum at 277 K, the solid phase (ice) is less denser than the liquid, and its thermodynamic response functions, such as the specific heat C_P and isothermal compressibility κ_T, also increase anomalously upon cooling. In the glassy state, water can exist in two different forms, low-density and high-density amorphous ice (LDA and HDA). While water has been scrutinized for many centuries, …

Quantifying Temperature-, Pressure-, And Nuclear Quantum Effects On Hydrophobic And Hydrophilic Water-Mediated Interactions, Justin T. Engstler

Dissertations, Theses, and Capstone Projects

Water-mediated interactions (WMIs) are responsible for diverse processes in aqueous solutions, including protein folding and nanoparticle aggregation. WMI may be affected by changes in temperature and pressure, and hence, they can alter chemical/physical processes that occur in aqueous environments. Traditionally, attention has been focused on hydrophobic interactions while, in comparison, the role of hydrophilic and hybrid (hydrophobic–hydrophilic) interactions have been mostly overlooked. Here, we study the role of T and P on the WMI between nanoscale (i) hydrophobic–hydrophobic, (ii) hydrophilic–hydrophilic, and (iii) hydrophilic–hydrophobic pairs of (hydroxylated/non-hydroxylated) graphene-based surfaces. We find that hydrophobic, hydrophilic, and hybrid interactions are all sensitive to …

Centrality Effects On Heavy-Flavor Quark Production And Invariant Yield In Phenix Proton–Gold Collisions At Center-Of-Mass Energy 200 Gev, And Assembly, Testing, Calibration, And Installation Of The Sphenix Hadronic Calorimeters, Daniel Richford

Dissertations, Theses, and Capstone Projects

Hadrons created in heavy-ion collisions interact with the open color-charge of the quark-gluon plasma through their constituent quarks. The medium imparts substantial modifications to heavy-flavor hadrons' momentum spectra. For collisions of small systems, the centrality of those collisions affects both the production of heavy-quarks and the medium modifications that the heavy-quarks experience. This analysis uses the PHENIX detector at the Relativistic Heavy Ion Collider, which collected data from proton--gold collisions in 2015, with a trigger to preference the collection of the five-percent most-central collisions. This analysis uses the distance-of-closest-approach of electron tracks to study semileptonic decays from charm and bottom …

Dynamics Of Spin And Charge Of Color Centers In Diamond Under Cryogenic Conditions, Richard G. Monge

Dissertations, Theses, and Capstone Projects

Individual quantum systems in semiconductors are currently the most sought-after platform for applications in quantum science. Most notably, the nitrogen-vacancy (NV) center in diamond features a defect deep within the electronic bandgap, making it amenable for precise manipulation to help pave the way to perform fundamental quantum physics experimentation. The NV center also offers long coherence times and versatile spin-dependent fluorescent properties, making it an ideal candidate for a nanoscale magnetometer. Furthermore, multi-color excitation offers deterministic charge state manipulation. While ambient operation has been key to their appeal, bringing NVs to cryogenic conditions opens new opportunities for alternate forms of …

Phase Transitions And Thermal Stability Of The Magnetic Dual Chiral Density Wave Phase In Cold, Dense Qcd, William G. Gyory

Dissertations, Theses, and Capstone Projects

The correct description of strongly interacting matter at extreme densities and low temperatures remains poorly understood. We analyze the magnetic dual chiral density wave (MDCDW) phase, an inhomogeneous chiral condensate that arises in cold, dense quark matter in a magnetic field. We first review the background theory and derive the free energy of the condensate. Then we show how the phase transitions can be studied using a generalized Ginzburg-Landau expansion, and we derive a convenient all-orders formula for the coefficients. Using these tools, we compute the order parameters, critical temperature, and threshold temperature over a range of chemical potentials and …

Tunable Linear And Nonlinear Metasurfaces Based On Hybrid Gold-Graphene Plasmons, Matthew Feinstein

Dissertations, Theses, and Capstone Projects

Optical Metasurfaces are planar structures that are patterned with subwavelength structures and are very thin compared to the wavelength of light. Despite their thinness, these structured materials can strongly interact with incident light to effect the functionalities of conventional optical components, such as rotation of the polarization state, beam steering, lensing, spectral filtering, and holography, to name a few. Metasurfaces can also facilitate nonlinear optical effects, such as the mixing of beams at different frequencies to generate a beam at a new frequency.

The ability to alter the behavior of a metasurface during operation is highly desired for applications such …

Syllabus For Computational Physics (Phys 39907), Mark D. Shattuck

Open Educational Resources

Syllabus for City College of New York Computational Physics course.

Hydrodynamic And Physicochemical Interactions Between An Active Janus Particle And An Inactive Particle, Jessica S. Rosenberg

Dissertations, Theses, and Capstone Projects

Active matter is an area of soft matter science in which units consume energy and turn it into autonomous motion. Groups of these units – whether flocks of birds, bacterial colonies, or even collections of synthetically-made active particles – may exhibit complex behavior on large scales. While the large-scale picture is of great importance, so is the microscopic scale. Studying the individual particles that make up active matter will allow us to understand how they move, and whether and under what circumstances their activity can be controlled.

Here we delve into the world of active matter by studying colloidal-sized (100 …

The Study Of Excitons In 2d Novel Materials And Their Van Der Waals Heterostructures In The Magnetic Field, Anastasia Spiridonova

Dissertations, Theses, and Capstone Projects

This research focuses on the direct and indirect excitons in Rydberg states in monolayers, bilayers, and van der Waals heterostructures composed of 2D semiconductors in the presence of the external magnetic field. In our work, we report binding energies of direct and indirect excitons in Rydberg states, the energy contribution from the magnetic field to the binding energies of magnetoexcitons, and diamagnetic coefficients (DMCs) of magnetoexcitons.

We study isotropic materials: transition metal dichalcogenides, TMDCs (WSe₂, WS₂, MoSe₂, MoS₂), and Xenes (silicene, germanene, stanene), and anisotropic materials: phosphorene and transition metal trichalcogenides, TMTCs …

Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown

Dissertations, Theses, and Capstone Projects

This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …

Dynamics In Designed Elastins And Enzymes, Jonathan M. Preston

Dissertations, Theses, and Capstone Projects

In this dissertation I present experimental results on the structure and dynamics of elastin, an elastomeric extracellular component in vertebrates that, in mammals, provides structure and elasticity to the circulatory system, lungs, skin and joints. These experiments, using a set of designed elastin like proteins with properties analogous to the natural protein, show that elastin is highly disordered and connect this disorder to its mechanism of assembly and elasticity. In addition, I also present preliminary work on imparting flexibility into a set of computationally designed metalloenzymes to broaden the range of catalytic activities they perform.

One-Loop Corrections To Dihadron Production In Dis At Small X, Filip Bergabo

Dissertations, Theses, and Capstone Projects

We calculate the one-loop corrections to dihadron production in Deep Inelastic Scattering (DIS) at small x using the Color Glass Condensate formalism. We show that all UV and soft singularities cancel while the collinear divergences are absorbed into quark and anti quark-hadron fragmentation functions. Rapidity divergences lead to JIMWLK evolution of dipoles and quadrupoles describing multiple-scatterings of the quark anti-quark dipole on the target proton/nucleus. The resulting cross section is finite and can be used for phenomenological studies of dihadron angular correlations at small x in a future Electron-Ion Collider (EIC).

Beam-Based Target Alignment For Mu2e, Helenka Casler

Dissertations, Theses, and Capstone Projects

The Mu2e Experiment is a precision experiment at Fermi National Accelerator Laboratory, searching for charged lepton flavor violation (CLFV) in the conversion of a muon to an electron in the presence of an atomic nucleus. In order to achieve the expected single-event sensitivity of 3 × 10^-17 , Mu2e will require an intense muon beam, generated via pion decay. These pions are the product of a proton beam striking a radiatively-cooled tungsten target. In order to maximize pion production and prevent target failure, the beam will have to be aligned with the target center to within 0.5 mm. The …

A Quantum Approach To Language Modeling, Constantijn Van Der Poel

Dissertations, Theses, and Capstone Projects

This dissertation consists of six chapters. . . Chapter 1: We introduce language modeling, outline the software used for this thesis, and discuss related work. Chapter 2: We will unpack the transition from classical to quantum probabilities, as well as motivate their use in building a model to understand language-like datasets. Chapter 3: We motivate the Motzkin dataset, the models we will be investigating, as well as the necessary algorithms to do calculations with them. Chapter 4: We investigate our models’ sensitivity to various hyperparameters. Chapter 5: We compare the performance and robustness of the models. Chapter 6: We conclude …

Revealing The Three-Dimensional Magnetic Texture With Machine Learning Models, Shihua Zhao

Dissertations, Theses, and Capstone Projects

Revealing three-dimensional (3D) magnetic textures with vector field electron tomography (VFET) is essential in studying novel magnetic materials with topologically protected spin textures potentially being used in the next-generation semiconductor industry. In this dissertation, we use machine learning (ML) models to reconstruct 3D magnetic textures from electron holography (EH) data.

We can feed the EH data, a series of two-dimensional (2D) phasemaps, into a neural network (NN) architecture directly or feed the EH data into a conventional VFET and then feed the reconstructed results into a NN. Thus, perceptive NN, either a simple convolutional neural network (CNN) or Unet architecture, …

Electromagnetic Theory And Applications, Nicholas Madamopoulos, George Kliros

Open Educational Resources

This book intends to provide both the fundamentals of Electromagnetics but also some practical applications of the concepts covered. Having taught electromagnetics for several years, the authors feel that many times the field of electromagnetics comes as “old” and often times students do not appreciate the concepts and their importance in everyday applications. The authors intend to accompany the EM concepts with life applications. Hence, students may see the direct impact of the knowledge they acquire through the study of the field of electromagnetics and better appreciate the field.

Phys 275: Intro To Scientific Computing, David Goldberg

Open Educational Resources

No abstract provided.

Perspectives On Determinism In Quantum Mechanics: Born, Bohm, And The “Quantal Newtonian” Laws, Viraht Sahni

Publications and Research

Quantum mechanics has a deterministic Schrödinger equation for the wave function. The Göttingen–Copenhagen statistical interpretation is based on the Born Rule that interprets the wave function as a “probability amplitude.” A precept of this interpretation is the lack of determinism in quantum mechanics. The Bohm interpretation is that the wave function is a source of a field experienced by the electrons, thereby attributing determinism to quantum theory. In this paper, we present a new perspective on such determinism. The ideas are based on the equations of motion or “Quantal Newtonian” Laws obeyed by each electron. These Laws, derived from …

Classical Mechanics, Mark D. Shattuck

Open Educational Resources

Syllabus for Classical Mechanics

Coupled Spherical-Cavities, Stanislav Kreps, Vladimir Shuvayev, Mark Douvidzon, Baheej Bathish, Tom Lenkiewicz Abudi, Amirreza Ghaznavi, Jie Xu, Yang Lin, Lev Deych, Tal Carmon

Publications and Research

In this work, we study theoretically and experimentally optical modes of photonic molecules—clusters of optically coupled spherical resonators. Unlike previous studies, we do not use stems to hold spheres in their positions relying, instead on optical tweezers to maintain desired structures. The modes of the coupled resonators are excited using a tapered fiber and are observed as resonances with a quality factor as high as 107. Using the fluorescent mapping technique, we observe families of coupled modes with similar spatial and spectral shapes repeating every free spectral range (a spectral separation between adjacent resonances of individual spheres). Experimental results are …

Whispering Gallery Modes Of A Triatomic Photonic Molecule, Vladimir Shuvayev, Stanislav Kreps, Tal Carmon, Lev Deych

Publications and Research

In this paper, we present the results of numerical simulations of the optical spectra of a three-sphere photonic molecule. The configuration of the system was continuously modified from linear to triangular, in-plane with the fundamental mode excited in one of the spheres and perpendicular to it. We found the relative insensitivity of the spectra to the in-plane deviation from the linear arrangement up to about 110°. For larger angles, the spectra show significant modification consisting of the major spectral peaks splitting and shifting. On the contrary, the spectra are quite sensitive to out-of-plane molecule deviation, even at small angles. Thus, …