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Articles 1 - 30 of 2387
Full-Text Articles in Physics
Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon
Binding Energy Of Muonic Beryllium: Perturbative Versus All-Order Calculations, Shikha Rathi, Ulrich D. Jentschura, Paul Indelicato, Ben Ohayon
Physics Faculty Research & Creative Works
We compute the ground-state binding energy of muonic (Formula presented) (Formula presented) Be in two ways: first, the fully perturbative treatment of the nuclear-size effect often employed in light systems, and second, an approach that accounts for the finite-nuclear-size to all orders (and is inspired by calculations otherwise employed for heavy muonic ions). The results are compared term by term and show that both approaches agree to better than one part-per-million of the total energy. The objective of this work is twofold. The first is practical: to provide a parameterization that allows the extraction of the (Formula presented) (Formula presented) …
Phases And Dynamics Of An Impurity Immersed In One-Dimensional Quantum Droplets, Dimitrios Diplaris, Ilias A. Englezos, Friethjof Theel, Peter Schmelcher, Simeon I. Mistakidis
Phases And Dynamics Of An Impurity Immersed In One-Dimensional Quantum Droplets, Dimitrios Diplaris, Ilias A. Englezos, Friethjof Theel, Peter Schmelcher, Simeon I. Mistakidis
Physics Faculty Research & Creative Works
We explore the ground-state properties of a single impurity immersed in a one-dimensional quantum droplet medium formed by a two-component Bose mixture. Relying on ab initio simulations, we demonstrate that tuning the impurity–droplet interactions allows to controllably reshape the droplets' density profiles and associated correlation patterns. For attractive impurity-medium couplings, the impurity becomes localized within the droplet, which exhibits a density hump at the vicinity of the impurity, while repulsive interactions facilitate phase separation. Comparing our many-body results with the appropriate extended Gross–Pitaevskii description, we find adequate agreement for the droplet density profiles, with the effective field approach systematically overestimating …
Golden And Silver Dark Sirens For Precise H0 Measurement With Hetdex, Yixuan Dang, Ish Gupta, Robin Ciardullo, Erin Mentuch Cooper, Shiksha Pandey, Dustin Davis, Surhud More, Rachel Gray, Hsin Yu Chen, Daniel J. Farrow, Caryl Gronwall, Donghui Jeong, Shun Saito, Donald P. Schneider
Golden And Silver Dark Sirens For Precise H0 Measurement With Hetdex, Yixuan Dang, Ish Gupta, Robin Ciardullo, Erin Mentuch Cooper, Shiksha Pandey, Dustin Davis, Surhud More, Rachel Gray, Hsin Yu Chen, Daniel J. Farrow, Caryl Gronwall, Donghui Jeong, Shun Saito, Donald P. Schneider
Physics Faculty Research & Creative Works
Gravitational waves (GWs) from compact binary coalescences are standard sirens that provide a direct measure of the source's luminosity distance, enabling an independent measurement of the Hubble constant (H0). While a bright siren—a GW event with an identified electromagnetic (EM) counterpart—provided the first such constraint, most detections, currently dominated by black hole mergers, lack EM signatures. A measurement of H0 is still possible with these dark sirens by statistically associating GW events with galaxies in existing catalogs based on the sky localization. In this work, we explore the potential of two subsets of dark sirens categorized by their localization precision: …
Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau
Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau
Chemistry Faculty Research & Creative Works
In the interstellar medium (ISM), non-local thermodynamic equilibrium situations are common due to low density, and one needs to consider the effect of molecular collisions in order to interpret the observations. Among the species detected in the ISM, cyanopolyynes, with the general molecular formula HC2n+1N (n = 1, 2, …), are characterized by large dipole moments and small rotational constants and constitute an indispensable class of candidates for the sensitive tracers of local density and temperature. We present a study of the collisional (de-) excitation of HC5N by para-H2 (p-H2) in its ground …
Harnessing Wavefront Shaping Control For Sensing Applications, Pablo Jara
Harnessing Wavefront Shaping Control For Sensing Applications, Pablo Jara
Miners Solving for Tomorrow Research Conference
Diffuse optical tomography (DOT) and functional near-infrared spectroscopy (fNIRS) enable deep, non-invasive sensing in biological tissue but are fundamentally limited by the photon budget - most injected light is lost to scattering before reaching the detector. Wavefront shaping (WFS) can enhance signal strength inside scattering media via interference, but the conventional diffusion-based sensitivity model breaks down under coherent illumination. We develop a microscopic theory of optical sensitivity that captures interference effects neglected by diffusion theory. We prove analytically that the microscopic and diffusive descriptions coincide under random illumination and identify WFS strategies that enhance sensitivity beyond this limit. The maximum …
Dispersive Shock And Rogue Waves In Two-Dimensional Quantum Droplets, Farhana Bristy
Dispersive Shock And Rogue Waves In Two-Dimensional Quantum Droplets, Farhana Bristy
Miners Solving for Tomorrow Research Conference
Quantum droplets, are liquid type configurations stabilized by the balance between attractive mean-field interactions and repulsive quantum fluctuations. They provide highly flexible platforms for the quantum simulation of hydrodynamic phenomena using ultracold gases. Here, we explore the nonlinear quantum dynamics of two-dimensional quantum droplets under Riemann initial conditions. The steepness of the latter facilitates the emergence of radially symmetric dispersive shock waves (DSWs) when quantum fluctuations dominate. In particular, the ensuing DSWs travel from the potential edges toward the center where they collide and through their interference high amplitude spatially localized rogue wave structures emerge. In contrast, tuning the interactions …
Direct Energy Cascade Of 2d Quantum Turbulence In Supersolids, Lukas Farthing
Direct Energy Cascade Of 2d Quantum Turbulence In Supersolids, Lukas Farthing
Miners Solving for Tomorrow Research Conference
The non-equilibrium turbulent response of periodically driven three-dimensional ultracold dipolar gases is induced by an external time-dependent ring potential. To model this system and monitor its non-equilibrium quantum dynamics, we invoke an extended Gross-Pitaevskii framework containing the first-order quantum correction to the mean-field energy functional. The shape of the external perturbing potential is chosen to trigger angular roton excitations, driving the supersolid configuration out of equilibrium and attaining a turbulent state. Following the generation of shallow vortical defects in the bulk, a direct cascade front manifests, transporting energy from larger to smaller length scales. This leads to a non-equilibrium quasi-steady …
Vortex Generation In Dipolar Supersolids, Jacob Harl
Vortex Generation In Dipolar Supersolids, Jacob Harl
Miners Solving for Tomorrow Research Conference
Ultracold atomic gases offer highly tunable platforms for exploring complex quantum many-body phenomena. In addition, dipolar quantum gases of magnetic atoms featuring long-range anisotropic interactions are exquisite systems for realizing exotic phases-of-matter in an experimentally controlled way. A prototypical example is the supersolid state which simultaneously exhibits frictionless flow of superfuids and crystalline density modulation of solids. In this realm, we investigate the dynamical generation of vortex topological defects by imprinting a suitable phase jump in quasi-two-dimensional dipolar supersolids. This protocol enables the nucleation of a dark soliton which consecutively becomes unstable via the eponymous snake instability due to its …
Elucidating Complex H Behavior In Amorphous Oxide Semiconductors By Machine Learning, Lucas Ethington
Elucidating Complex H Behavior In Amorphous Oxide Semiconductors By Machine Learning, Lucas Ethington
Miners Solving for Tomorrow Research Conference
In this project, the disordered oxide structures will be mapped by a machine-learning algorithm (e.g., HDBSCAN) to identify characteristic behaviors of the proton across different material densities and defect types. This should help identify the under-coordinated, highly distorted, weakly-bonded, and dynamically unstable atoms to predict the most probable H locations. This fast and accurate prediction of energetically favorable H distribution will enable a reliable and fast screening of a large number of AOSs with variable cation and/or anion compositions. The approach will help find AOSs with suppressed numbers of M-OH defects (that form deep electron traps, limiting the number of …
The Structure Of Amorphous Alox And Its Role In H Distribution And Dynamics, Lana Herkenhoff
The Structure Of Amorphous Alox And Its Role In H Distribution And Dynamics, Lana Herkenhoff
Miners Solving for Tomorrow Research Conference
Hydrogen is known to be the culprit of electron decoherence in Josephson junctions, greatly affecting the performance of superconducting quantum circuits. For Al/AlOx interfaces, the challenge is two-fold: 1) similar Al-Al and Al-H bond strength promotes bond switching and, hence, facilitates vigorous H motion; whereas 2) oxygen has only a slight preference to form Al-O rather than H-O bond, implying that (meta)stable Al--O-H are likely to occur, especially in a disordered oxide. In this project, ab initio molecular dynamics (MD) simulations are employed to generate the atomistic models of Al2O3-x with oxygen vacancy defects and to quantify the H diffusion, …
Dynamical Transition From A Two-Dimensional Soliton To A Rogue Wave In Quantum Droplets, Punit Sesha Sai Turlapati
Dynamical Transition From A Two-Dimensional Soliton To A Rogue Wave In Quantum Droplets, Punit Sesha Sai Turlapati
Miners Solving for Tomorrow Research Conference
We investigate the nonequilibrium dynamics of two-dimensional quantum droplets: ultracold self-bound many-body states stabilized by the interplay of mean-field attractive interactions and repulsive quantum fluctuations. Flat-top ground state droplets are subject to an external potential, an attractive well and a repulsive barrier. Under the influence of the attractive well, we observe signatures of a Townes soliton formation, which for increasing strength of the well transitions into a two-dimensional rogue wave structure, a time-periodic highly localized configuration with amplitude three times larger than the background. The barrier instead favors a dynamical splitting of the droplet. We have developed a parallelized simulation …
Correlated Many-Body Quantum Dynamics Of The Peregrine Soliton, D. Diplaris, G. A. Bougas, P. G. Kevrekidis, C. L. Hung, P. Schmelcher, S. I. Mistakidis
Correlated Many-Body Quantum Dynamics Of The Peregrine Soliton, D. Diplaris, G. A. Bougas, P. G. Kevrekidis, C. L. Hung, P. Schmelcher, S. I. Mistakidis
Physics Faculty Research & Creative Works
We explore the correlated dynamics underlying the formation of the quantum Peregrine soliton, a prototypical rogue-wave excitation, utilizing interaction quenches from repulsive to attractive couplings in an ultracold bosonic gas confined in a one-dimensional box trap. The latter emulates the so-called semiclassical initial conditions and the associated gradient catastrophe scenario facilitating the emergence of a high-density, doubly localized waveform. The ensuing multiorbital variant of the Peregrine soliton features notable deviations from its mean-field sibling, including a reduced peak amplitude, wider core, absence of the side density dips, and earlier formation times. Moreover, Peregrine soliton generation yields coherence losses, while experiencing …
Ac Magnetic Measurements With A Self-Oscillating Lc Circuit And Its Application To University Education, Harshit Agarwal, Oleksandra Uralska, Jasmin Billingsley, Maxim Yamilov, Hyunsoo Kim
Ac Magnetic Measurements With A Self-Oscillating Lc Circuit And Its Application To University Education, Harshit Agarwal, Oleksandra Uralska, Jasmin Billingsley, Maxim Yamilov, Hyunsoo Kim
Physics Faculty Research & Creative Works
Editor's Note: This paper is a welcome tutorial on a technique for AC magnetometry, allowing the measurement of a sample's magnetic susceptibility with considerable sensitivity. The authors present a low-cost setup based on an LC self-oscillator circuit, which has an operating frequency that is rather sensitive to the susceptibility of a sample introduced within its inductor. After characterizing the performance of the circuit, data taken on a high-temperature superconducting sample are presented, demonstrating how the samples superconducting transition can be detected by this noncontact magnetic method, independent of the usual resistivity-based detection. This project will be of interest to instructors …
Precision Spectroscopy Of 2s-Ns Transitions In Atomic Hydrogen: A Determination Of The Proton Charge Radius, R. G. Bullis, W. L. Tavis, M. R. Weiss, Orellana O. Cisneros, A. J. Cheeseman, Ulrich D. Jentschura, D. C. Yost
Precision Spectroscopy Of 2s-Ns Transitions In Atomic Hydrogen: A Determination Of The Proton Charge Radius, R. G. Bullis, W. L. Tavis, M. R. Weiss, Orellana O. Cisneros, A. J. Cheeseman, Ulrich D. Jentschura, D. C. Yost
Physics Faculty Research & Creative Works
We present absolute frequency measurements of 2S1/2-nS1/2 two-photon transitions with n=8, 9, and 10 in a cryogenic beam of atomic hydrogen. Each transition has been measured with a fractional uncertainty of ≈2.6x10-12. Combining the results from this Letter and the 1S1/2-2S1/2 transition frequency, we extract a root-mean-square proton radius of rp=0.8433(31) fm and a Rydberg frequency of cR∞=3 289 841 960 252.9(9.7) kHz. These are in good agreement with the CODATA 2022 recommended values.
Guiding Fast Ion Beam By Suppressing Secondary Ions, Yingli Xue, Junliang Liu, Mingwu Zhang, Daniel Fischer, Guoxing Xia, Nikolaus Stolterfoht, Reinhold Schuch, Yehong Wu, Bian Yang, Xiaoxiao Li, Caojie Shao, Wei Wang, Zhangyong Song, Xing Fang
Guiding Fast Ion Beam By Suppressing Secondary Ions, Yingli Xue, Junliang Liu, Mingwu Zhang, Daniel Fischer, Guoxing Xia, Nikolaus Stolterfoht, Reinhold Schuch, Yehong Wu, Bian Yang, Xiaoxiao Li, Caojie Shao, Wei Wang, Zhangyong Song, Xing Fang
Physics Faculty Research & Creative Works
We demonstrate that secondary ions sputtered from a macrocapillary's inner surface by the primary beam induce premature saturation of the guiding field, hindering fast ion guiding. By suppressing secondary ion sputtering with grooved surfaces, we achieve a guiding-field potential difference exceeding 1 kV, 2 orders of magnitude larger than previously achieved in stable ion guiding. This enables stable guiding of a 20-keV/q O5+ beam at offset angles up to 15°, with transmitted ions retaining their initial energy and charge state. A self-consistent field model accurately reproduces these results, revealing that guiding performance relies on managing secondary ions and the channel's …
Magnetic Field Tuned Magnetic Order And Metamagnetic Criticality In Nonstoichiometric Ceaubi2, Halyna Hodovanets, Hyunsoo Kim, Tristin Metz, Yasuyuki Nakajima, Christopher J. Eckberg, Kefeng Wang, Jie Yong, Shanta R. Saha, David Graf, Nicholas P. Butch, Thomas Vojta, Johnpierre Paglione
Magnetic Field Tuned Magnetic Order And Metamagnetic Criticality In Nonstoichiometric Ceaubi2, Halyna Hodovanets, Hyunsoo Kim, Tristin Metz, Yasuyuki Nakajima, Christopher J. Eckberg, Kefeng Wang, Jie Yong, Shanta R. Saha, David Graf, Nicholas P. Butch, Thomas Vojta, Johnpierre Paglione
Physics Faculty Research & Creative Works
We present a detailed study of magnetization, resistivity, heat capacity, and x-ray and neutron powder diffraction measurements performed on single crystals of nonstoichiometric CeAuBi2, Au deficiency 18%, a strongly correlated antiferromagnet with Néel temperature TN = 13.2 K. Field-dependent magnetization measurements reveal a large magnetic anisotropy at low temperatures with an easy axis along the crystallographic c axis, in which direction a spin-flop transition exhibits strong features in magnetization, specific heat, and resistivity at Hc = 75 kOe. The constructed temperature-field phase diagram connects this transition to the suppression of magnetic order, which evolves from a …
Long-Range Fit: A Software Package For The Representation And Study Of Long-Range Molecular Interactions, Adrian L. Batista-Planas, Ernesto Quintas-Sánchez, Richard Dawes
Long-Range Fit: A Software Package For The Representation And Study Of Long-Range Molecular Interactions, Adrian L. Batista-Planas, Ernesto Quintas-Sánchez, Richard Dawes
Chemistry Faculty Research & Creative Works
Describing intermolecular forces is fundamental to modeling and predicting the behavior of molecular systems. In particular, long-range molecular interactions with electrostatic, induction, and dispersion as the main components play a critical role, especially for low-temperature and low-density regimes. Long-range interactions are often described through perturbation theory, representing the electronic charge distribution via a multipolar series of the moments and polarizability tensors corresponding to each molecule. However, while the theory is well established, obtaining the resulting analytical expressions (and their practical implementation) constitutes a highly complex and system-dependent task. To address this challenge, we developed long-range-fit (LRF), an interactive and user-friendly …
Rogue Waves In Extended Gross-Pitaevskii Models With A Lee-Huang-Yang Correction, Sathyanarayanan Chandramouli, S. I. Mistakidis, G. C. Katsimiga, D. J. Ratliff, D. J. Frantzeskakis, P. G. Kevrekidis
Rogue Waves In Extended Gross-Pitaevskii Models With A Lee-Huang-Yang Correction, Sathyanarayanan Chandramouli, S. I. Mistakidis, G. C. Katsimiga, D. J. Ratliff, D. J. Frantzeskakis, P. G. Kevrekidis
Physics Faculty Research & Creative Works
We explore the existence and dynamical generation of rogue waves (RWs) within a one-dimensional quantum droplet-bearing environment. RWs are computed by deploying a space-time fixed point scheme to the relevant extended Gross-Pitaevskii equation (eGPE). Parametric regions where the ensuing RWs are different from their counterparts in the nonlinear Schrödinger equation are identified. To corroborate the controllable generation—relevant to ultracold atom experiments—of these rogue patterns, we exploit two different protocols. The first is based on interfering dam break flows emanating from Riemann initial conditions, and the second refers to the gradient catastrophe of a spatially localized waveform. A multitude of possible …
Enhanced Superconductivity And Vortex Dynamics In Quasi-1d Tas2 Nanowires, Mathew Pollard, Visakha Ho, Clarissa Wisner, Eric W. Bohannan, Yew San Hor
Enhanced Superconductivity And Vortex Dynamics In Quasi-1d Tas2 Nanowires, Mathew Pollard, Visakha Ho, Clarissa Wisner, Eric W. Bohannan, Yew San Hor
Chemistry Faculty Research & Creative Works
We report the synthesis of high-quality 2H-TaS2 nanowires via a controlled two-step conversion process from TaS3 precursors, achieving robust superconductivity with a transition temperature T c ≈ 3.6K, which is significantly higher than bulk 2H-TaS2 (T c ≈ 0.8K). Structural and compositional analyses confirm phase purity and preserved one-dimensional morphology, while magneto transport measurements reveal an enhanced upper critical field μ 0 H c2 (2K)≈5 T, far exceeding the bulk value (μ0Hc2 (0)≈1.17T), attributed to dimensional confinement and suppression of charge-density wave order. Magnetic characterization demonstrates complex vortex dynamics, including flux jumps and a …
Quantum Critical Behavior Of Diluted Quasi-One-Dimensional Ising Chains, Logan Sowadski, Thomas Vojta
Quantum Critical Behavior Of Diluted Quasi-One-Dimensional Ising Chains, Logan Sowadski, Thomas Vojta
Physics Faculty Research & Creative Works
(Formula presented.) (Formula presented.) is a unique magnetic material. It features bulk 3D magnetic order at low temperatures, but its quantum critical behavior in a magnetic field is well described by the 1D transverse-field Ising universality class. This behavior is facilitated by the structural arrangement of magnetic (Formula presented.) ions in nearly isolated zig-zag chains. In this work, we investigate the effect of random site dilution on the critical properties of such a quasi-1D quantum Ising system. To this end, we introduce an anisotropic site-diluted 3D transverse-field Ising model. We find that site dilution leads to unconventional activated scaling behavior …
Generation Of Wave Turbulence In Dipolar Gases Driven Across Their Phase Transitions, Georgios A. Bougas, Koushik Mukherjee, Simeon Mistakidis
Generation Of Wave Turbulence In Dipolar Gases Driven Across Their Phase Transitions, Georgios A. Bougas, Koushik Mukherjee, Simeon Mistakidis
Physics Faculty Research & Creative Works
Ultracold quantum gases with long-range anisotropic interactions host novel exotic phases of matter, such as super solids, exhibiting both rigid and superfluid characteristics. The impact of this interplay on the out-of-equilibrium dynamics of dipolar gases, and in particular its connection with universal turbulent behavior, remains highly unexplored. Here, upon considering a dipolar Bose-Einstein condensate of dysprosium atoms being dynamically driven across the super solid-superfluid phase transition and vice versa, we unveil the emergence of a robust nonequilibrium quasi-steady state. This state displays self-similar momentum distributions exhibiting algebraic decay at large momenta, with scaling exponents supporting the existence of wave turbulence. …
Temperature-Dependent Dielectric Function Of Solids From Coupled Oscillators With Radiation Reaction: Application To Atom–Surface Interactions, Tuhin Kanti Das
Temperature-Dependent Dielectric Function Of Solids From Coupled Oscillators With Radiation Reaction: Application To Atom–Surface Interactions, Tuhin Kanti Das
Doctoral Dissertations
In this dissertation, we propose a uniform functional form of the dielectric function of solids that is applicable over a wide range of frequencies. We apply our model to describe the dielectric function of two technologically important materials: silicon and calcium fluoride. The temperature dependence of their dielectric functions is also described using simple analytic forms. We found that a generalized Sellmeier-type model with complex denominators (“damped oscillators”) does not lead to a satisfactory fit of experimental data for the dielectric function. In contrast, our model, which is analytically only slightly more involved (“complex oscillator strengths”, complex numerators), allows us …
Fully Differential Studies On Dissociative Capture In P + D2 Collisions And On Ionization In P + He Collisions, Shruti Majumdar
Fully Differential Studies On Dissociative Capture In P + D2 Collisions And On Ionization In P + He Collisions, Shruti Majumdar
Doctoral Dissertations
Advancing our understanding of few-body dynamics in simple atomic systems is a fundamental objective in atomic scattering research. The underlying problem is that the Schrödinger equation is not analytically solvable for more than two mutually interacting particles. This involves a comprehensive exploration of various channels, such as ionization, capture, and excitation. A common theoretical approach to describe ion-atom collisions is based on perturbation theory, where the scattering amplitude is expanded in powers of the interaction potential. Here, understanding the few-body problem means accurately describing the relative importance of the higher- vs the first order terms.
In the case of ionization, …
Relativistic And Recoil Corrections To Light-Fermion Vacuum Polarization For Bound Systems Of Spin-0, Spin-1=2, And Spin-1 Particles, Gregory S. Adkins, Ulrich D. Jentschura
Relativistic And Recoil Corrections To Light-Fermion Vacuum Polarization For Bound Systems Of Spin-0, Spin-1=2, And Spin-1 Particles, Gregory S. Adkins, Ulrich D. Jentschura
Physics Faculty Research & Creative Works
In bound systems whose constituent particles are heavier than the electron, the dominant radiative correction to energy levels is given by light-fermion (electronic) vacuum polarization. In consequence, relativistic and recoil corrections to the one-loop vacuum-polarization correction are phenomenologically relevant. Here, we generalize the treatment, previously accomplished for systems with orbiting muons, to bound systems of constituents with more general spins: spin-0, spin-1=2, and spin-1. We discuss the application of our more general expressions to various systems of interest, including spinless systems (pionium), muonic hydrogen and deuterium, and devote special attention to the excited non-S states of deuteronium, the bound system …
First Remi Experiments At A Cryogenic Ion Storage Ring, M. Schulz, F. Herrmann, W. Zhang, A. Dorn, M. Grieser, F. Grussie, H. Kreckel, O. Novotny, A. Wolf, T. Pfeifer, C. D. Schröter, R. Moshammer
First Remi Experiments At A Cryogenic Ion Storage Ring, M. Schulz, F. Herrmann, W. Zhang, A. Dorn, M. Grieser, F. Grussie, H. Kreckel, O. Novotny, A. Wolf, T. Pfeifer, C. D. Schröter, R. Moshammer
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
We have recorded double, triple, and quadruple coincidences between neutralized projectiles, recoiling target ions, and two electrons created in collisions of slow anions with neutral atoms. The experiments were performed at the cryogenic storage ring in Heidelberg. The recoil ions and ejected electrons were momentum-analyzed using a Reaction Microscope (ReMi) spectrometer. Various processes involving electron detachment from the projectile accompanied by various transitions in the target were investigated. Detachment without any transition in the target is qualitatively well described by a quasi-free electron model in the case of an Ar target. In detachment with single target ionization, no signatures of …
Emergent Spin Fluctuation And Structural Metastability In Self-Intercalated Cr1+Xte2 Compounds, Clayton Conner, Ali Sarikhani, Theo Volz, Mathew Pollard, Mitchel Vaninger, Xiaoqing He, Steven Kelley, Jacob Cook, Avinash Sah, John Clark, Hunter Lucker, Cheng Zhang, Paul Miceli, Yew San Hor
Emergent Spin Fluctuation And Structural Metastability In Self-Intercalated Cr1+Xte2 Compounds, Clayton Conner, Ali Sarikhani, Theo Volz, Mathew Pollard, Mitchel Vaninger, Xiaoqing He, Steven Kelley, Jacob Cook, Avinash Sah, John Clark, Hunter Lucker, Cheng Zhang, Paul Miceli, Yew San Hor
Physics Faculty Research & Creative Works
Intercalated van der Waals (vdW) magnetic materials host unique magnetic properties due to the interplay of competing interlayer and intralayer exchange couplings, which depend on the intercalant concentration within the van der Waals gaps. Magnetic vdW compound chromium telluride, (Formula presented.), has demonstrated rich magnetic phases at various Cr concentrations, such as the coexistence of ferromagnetic and antiferromagnetic phases in (Formula presented.) (equivalently, (Formula presented.)). The compound is created by intercalating 0.25 Cr atom per unit cell within the van der Waals gaps of (Formula presented.). In this work, we report a notably increased Curie Temperature and an emergent in-plane …
Tuning A Magnetic Energy Scale With Pressure And Field In Ute2, Hyunsoo Kim, I. Lin Liu, Wen Chen Lin, Yun Suk Eo, Sheng Ran, Nicholas P. Butch, Johnpierre Paglione
Tuning A Magnetic Energy Scale With Pressure And Field In Ute2, Hyunsoo Kim, I. Lin Liu, Wen Chen Lin, Yun Suk Eo, Sheng Ran, Nicholas P. Butch, Johnpierre Paglione
Physics Faculty Research & Creative Works
When a fragile ordered state is suppressed to zero temperature, a quantum phase transition occurs, which is often marked by the appearance of unconventional superconductivity. While the quantum critical point can be hidden, the influence of the quantum criticality extends to fairly high temperatures, manifesting non-Fermi liquid behavior in a wide range of the field-temperature-pressure phase space. Here, we report the tuning of a magnetic energy scale in the heavy-fermion superconductor UTe2, previously identified with a peak in the c-axis electrical transport temperature dependence, using applied hydrostatic pressures and a-axis-oriented magnetic fields as complementary (and opposing) tuning parameters: …
Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger
Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger
Physics Faculty Research & Creative Works
This article provides an overview of the current state of machine learning in gravitational-wave research with interferometric detectors. Such applications are often still in their early days but have reached sufficient popularity to warrant an assessment of their impact across various domains, including detector studies, noise and signal simulations, and the detection and interpretation of astrophysical signals. In detector studies, machine learning could be useful to optimize instruments like LIGO, Virgo, KAGRA, and future detectors. Algorithms could predict and help in mitigating environmental disturbances in real time, ensuring detectors operate at peak performance. Furthermore, machine-learning tools for characterizing and cleaning …
Time-Resolved 3d Momentum Spectroscopy In Continuous Wave Atomic Photoionization Experiments, K. L. Romans, B. P. Acharya, A. H.N.C.De Silva, K. Foster, O. Russ, Daniel Fischer
Time-Resolved 3d Momentum Spectroscopy In Continuous Wave Atomic Photoionization Experiments, K. L. Romans, B. P. Acharya, A. H.N.C.De Silva, K. Foster, O. Russ, Daniel Fischer
Physics Faculty Research & Creative Works
An experimental continuous-wave (cw) pump-probe scheme is demonstrated by investigating the population and photoionization dynamics of an atomic system. In particular, 6Li atoms are initially prepared in optically pumped 22S1/2 and 22P3/2 states before being excited via multi-photon absorption from a tunable femtosecond laser. The subsequent cascade back to the ground state is analyzed by ionizing the atoms in the field of a cw optical dipole trap laser. Conventional spectroscopic methods, such as standard cold-target recoil ion momentum spectroscopy or velocity map imaging, cannot provide simultaneous momentum and time-resolved information on an event-by-event basis for the system investigated here. The …
Simulating Realistic Lyman-𝛼 Emitters Including The Effect Of Radiative Transfer, Hasti Khoraminezhad, Shun Saito, Max Gronke, Chris Byrohl
Simulating Realistic Lyman-𝛼 Emitters Including The Effect Of Radiative Transfer, Hasti Khoraminezhad, Shun Saito, Max Gronke, Chris Byrohl
Research Data
We present an empirical yet physically motivated simulation of realistic Lyman-𝛼 emitters (LAEs) at 𝑧 ∼ 2 − 3, crucial for ongoing and forthcoming cosmological LAE surveys. We combine an empirical UniverseMachine galaxy-halo model with a simple spherical expanding shell model for the Lyman-𝛼 radiative transfer, calibrating only three free parameters to simultaneously reproduce the observed Lyman-𝛼 luminosity function and the angular clustering. Our LAE model is further supported by its consistency with other observables such as the Lyman-𝛼 equivalent width distribution, the Lyman-𝛼 escape fraction as a function of stellar mass and dust reddening, and the systemic velocity offsets. …