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Full-Text Articles in Physics

Pattern Formation In One-Dimensional Polaron Systems And Temporal Orthogonality Catastrophe, Georgios M. Koutentakis, Simeon I. Mistakidis, Peter Schmelcher Mar 2022

Pattern Formation In One-Dimensional Polaron Systems And Temporal Orthogonality Catastrophe, Georgios M. Koutentakis, Simeon I. Mistakidis, Peter Schmelcher

Physics Faculty Research & Creative Works

Recent Studies Have Demonstrated That Higher Than Two-Body Bath-Impurity Correlations Are Not Important For Quantitatively Describing The Ground State Of The Bose Polaron. Motivated By The Above, We Employ The So-Called Gross Ansatz (GA) Approach To Unravel The Stationary And Dynamical Properties Of The Homogeneous One-Dimensional Bose-Polaron For Different Impurity Momenta And Bath-Impurity Couplings. We Explicate That The Character Of The Equilibrium State Crossovers From The Quasi-Particle Bose Polaron Regime To The Collective-Excitation Stationary Dark-Bright Soliton For Varying Impurity Momentum And Interactions. Following An Interspecies Interaction Quench The Temporal Orthogonality Catastrophe Is Identified, Provided That Bath-Impurity Interactions Are Sufficiently Stronger …


Long-Range Interactions For Hydrogen Atoms In Excited D States, Chandra M. Adhikari, Ulrich D. Jentschura Mar 2022

Long-Range Interactions For Hydrogen Atoms In Excited D States, Chandra M. Adhikari, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Pressure shifts inside an atomic beam are among the more theoretically challenging effects in high-precision measurements of atomic transitions. A crucial element in their theoretical analysis is the understanding of long-range interatomic interactions inside the beam. For excited reference states, the presence of quasi-degenerate states leads to additional challenges, due to the necessity to diagonalize large matrices in the quasi-degenerate hyperfine manifolds. Here, we focus on the interactions of hydrogen atoms in reference states composed of an excited nD state (atom A), and in the metastable 2S state (atom B). We devote special attention to the cases n = 3 …


Depth-Targeted Energy Delivery Deep Inside Scattering Media, Nicholas Bender, Alexey Yamilov, Arthur Goetschy, Hasan Yılmaz, Chia Wei Hsu, Hui Cao Mar 2022

Depth-Targeted Energy Delivery Deep Inside Scattering Media, Nicholas Bender, Alexey Yamilov, Arthur Goetschy, Hasan Yılmaz, Chia Wei Hsu, Hui Cao

Physics Faculty Research & Creative Works

Diffusion makes it difficult to predict and control wave transport through a medium. Overcoming wave diffusion to deliver energy into a target region deep inside a diffusive system is an important challenge for applications, but also represents an interesting fundamental question. It is known that coherently controlling the incident wavefront allows diffraction-limited focusing inside a diffusive system, but in many applications, the targets are significantly larger than a focus and the maximum deliverable energy remains unknown. Here we introduce the 'deposition matrix', which maps an input wavefront to the internal field distribution, and we theoretically predict the ultimate limit on …


Magic Wavelengths For 1s–Ns And 2s–Ns Transitions In Hydrogenlike Systems, Chandra M. Adhikari, Jonathan C. Canales, Thusitha P.W. Arthanayaka, Ulrich D. Jentschura Mar 2022

Magic Wavelengths For 1s–Ns And 2s–Ns Transitions In Hydrogenlike Systems, Chandra M. Adhikari, Jonathan C. Canales, Thusitha P.W. Arthanayaka, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We study the magic wavelength for two-photon 1S–nS transitions in a hydrogen and deuterium atom, as well as 2S–nS transitions, where the lower level is the metastable 2S state. At the magic wavelength, the dynamic Stark shifts of the ground and the excited state of the transition coincide, so that the transition frequency is independent of the intensity of the trapping laser field. Experimentally feasible magic wavelengths of transitions with small slopes in the atomic polarizabilities are determined; these are the most stable magic wavelengths against variations of the laser frequency. We provide data for the magic wavelengths for the …


Long-Range Interactions For Hydrogen Atoms In Excited D States, Chandra M. Adhikari, Ulrich D. Jentschura Mar 2022

Long-Range Interactions For Hydrogen Atoms In Excited D States, Chandra M. Adhikari, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Pressure shifts inside an atomic beam are among the more theoretically challenging effects in high-precision measurements of atomic transitions. A crucial element in their theoretical analysis is the understanding of long-range interatomic interactions inside the beam. For excited reference states, the presence of quasi-degenerate states leads to additional challenges, due to the necessity to diagonalize large matrices in the quasi-degenerate hyperfine manifolds. Here, we focus on the interactions of hydrogen atoms in reference states composed of an excited nD state (atom A), and in the metastable 2S state (atom B). We devote special attention to the cases n = 3 …


Fully Differential Investigation Of Two-Center Interference In Dissociative Capture In P+ H2 Collisions, S. Bastola, M. Dhital, B. Lamichhane, A. Silvus, R. Lomsadze, J. Davis, A.(Ahmad) Hasan, A. Igarashi, Michael Schulz Mar 2022

Fully Differential Investigation Of Two-Center Interference In Dissociative Capture In P+ H2 Collisions, S. Bastola, M. Dhital, B. Lamichhane, A. Silvus, R. Lomsadze, J. Davis, A.(Ahmad) Hasan, A. Igarashi, Michael Schulz

Physics Faculty Research & Creative Works

We Have Measured and Calculated Fully Differential Cross Sections for Vibrational Dissociation Following Capture in 75-KeV P+H2 Collisions. for a Molecular Orientation Perpendicular to the Projectile Beam Axis and Parallel to the Transverse Momentum Transfer We Observe a Pronounced Interference Structure. the Positions of the Interference Extrema Suggest that the Interference Term is Afflicted with a Phase Shift Which Depends on the Projectile Scattering Angle. However, No Significant Dependence on the Kinetic-Energy Release Was Observed. Considerable Discrepancies between Our Calculations and Experimental Data Were Found.


Effect Of Interfacial Atomic Mixing On The Thermal Conductivity Of Multi-Layered Stacking Structure, Yingguang Liu, Xinqiang Xue, Guoliang Ren, Aleksandr V. Chernatynskiy Feb 2022

Effect Of Interfacial Atomic Mixing On The Thermal Conductivity Of Multi-Layered Stacking Structure, Yingguang Liu, Xinqiang Xue, Guoliang Ren, Aleksandr V. Chernatynskiy

Physics Faculty Research & Creative Works

Multi-layered stacking structures and atomic mixing interfaces were constructed. The effects of various factors on the thermal conductivity of different lattice structures were studied by non-equilibrium molecular dynamics simulations, including the number of atomic mixing layers, temperature, total length of the system, and period length. The results showed that the mixing of two and four layers of atoms can improve the thermal conductivities of the multi-layer structure with a small total length due to a phonon "bridge" mechanism. When the total length of the system is large, the thermal conductivity of the multi-layer structure with atomic mixing interfaces decreases significantly …


High Harmonic Generation In Mixed Xuv And Nir Fields At A Free-Electron Laser, Jan Troß, Shashank Pathak, Adam Summers, Dimitrios Rompotis, Benjamin Erk, Christopher Passow, Bastian Manschwetus, Rebecca Boll, Patrik Grychtol, Sadia Bari, Vinod Kumarappan, Anh(Anh-Thu) Thu Le, Cheng Jin, Carlos Trallero Feb 2022

High Harmonic Generation In Mixed Xuv And Nir Fields At A Free-Electron Laser, Jan Troß, Shashank Pathak, Adam Summers, Dimitrios Rompotis, Benjamin Erk, Christopher Passow, Bastian Manschwetus, Rebecca Boll, Patrik Grychtol, Sadia Bari, Vinod Kumarappan, Anh(Anh-Thu) Thu Le, Cheng Jin, Carlos Trallero

Physics Faculty Research & Creative Works

We Present the Results of an Experiment Investigating the Generation of High-Order Harmonics by a Femtosecond Near-Infrared (NIR) Laser Pulse in the Presence of an Extreme Ultraviolet (XUV) Field Provided by a Free-Electron Laser (FEL), a Process Referred to as XUV-Assisted High-Order Harmonic Generation (HHG). Our Experimental Findings Show that the XUV Field Can Lead to a Small Enhancement in the Harmonic Yield When the XUV and NIR Pulses overlap in Time, while a Strong Decrease of the HHG Yield and a Red Shift of the HHG Spectrum is Observed When the XUV Precedes the NIR Pulse. the Latter Observations …


On-Demand Generation Of Dark-Bright Soliton Trains In Bose-Einstein Condensates, A. Romero-Ros, Garyfallia C. Katsimiga, P. G. Kevrekidis, B. Prinari, G. Biondini, P. Schmelcher Feb 2022

On-Demand Generation Of Dark-Bright Soliton Trains In Bose-Einstein Condensates, A. Romero-Ros, Garyfallia C. Katsimiga, P. G. Kevrekidis, B. Prinari, G. Biondini, P. Schmelcher

Physics Faculty Research & Creative Works

The controlled creation of dark-bright (DB) soliton trains in multicomponent Bose-Einstein condensates (BECs) is a topic of ongoing interest. In this work we generalize earlier findings on the creation of dark soliton trains in single-component BECs [A. Romero-Ros, Phys. Rev. A 103, 023329 (2021)2469-992610.1103/PhysRevA.103.023329] to two-component BECs. By choosing suitable filled box-type initial configurations (FBTCs) and solving the direct scattering problem for the defocusing vector nonlinear Schrödinger equation with nonzero boundary conditions we obtain analytical expressions for the DB soliton solutions produced by a general FBTC. It is found that the size of the initial box and the amount of …


Metallic Networks And Hydrogen Compensation In Highly Nonstoichiometric Amorphous In₂O₃₋ₓ, Julia E. Medvedeva, E. Caputa-Hatley, I. Zhuravlev Feb 2022

Metallic Networks And Hydrogen Compensation In Highly Nonstoichiometric Amorphous In₂O₃₋ₓ, Julia E. Medvedeva, E. Caputa-Hatley, I. Zhuravlev

Physics Faculty Research & Creative Works

The unique response of amorphous ionic oxides to changes in oxygen stoichiometry is investigated using computationally intensive ab initio molecular dynamics simulations, comprehensive structural analysis, and hybrid density-functional calculations for the oxygen defect formation energy and electronic properties of amorphous In2O3-x with x = 0-0.185. In marked contrast to nonstoichiometric crystalline nanocomposites with clusters of metallic inclusions inside an insulating matrix, the lack of oxygen in amorphous indium oxide is distributed between a large fraction of undercoordinated In atoms, leading to an extended shallow state for x < 0.037, a variety of weakly and strongly localized states for 0.074 < x < 0.148, and a percolation-like network of single-atom chains of metallic In-In bonds for x > 0.185. The calculated carrier concentration increases from 3.3 x 10 …


Metallic Networks And Hydrogen Compensation In Highly Nonstoichiometric Amorphous In2 O3-X, Julia E. Medvedeva, E. Caputa-Hatley, I. Zhuravlev Feb 2022

Metallic Networks And Hydrogen Compensation In Highly Nonstoichiometric Amorphous In2 O3-X, Julia E. Medvedeva, E. Caputa-Hatley, I. Zhuravlev

Physics Faculty Research & Creative Works

The unique response of amorphous ionic oxides to changes in oxygen stoichiometry is investigated using computationally intensive ab initio molecular dynamics simulations, comprehensive structural analysis, and hybrid density-functional calculations for the oxygen defect formation energy and electronic properties of amorphous In2O3-x with x=0-0.185. In marked contrast to nonstoichiometric crystalline nanocomposites with clusters of metallic inclusions inside an insulating matrix, the lack of oxygen in amorphous indium oxide is distributed between a large fraction of undercoordinated In atoms, leading to an extended shallow state for x0.185. The calculated carrier concentration increases from 3.3x1020cm-3 at x=0.037 to 6.6x1020cm-3 at x=0.074 and decreases …


Characterization Of Single-Shot Attosecond Pulses With Angular Streaking Photoelectron Spectra, Xi Zhao, Siqi Li, Taran Driver, Van Hung Hoang, Anh-Thu Le, James P. Cryan, Agostino Marinelli, C. D. Lin Jan 2022

Characterization Of Single-Shot Attosecond Pulses With Angular Streaking Photoelectron Spectra, Xi Zhao, Siqi Li, Taran Driver, Van Hung Hoang, Anh-Thu Le, James P. Cryan, Agostino Marinelli, C. D. Lin

Physics Faculty Research & Creative Works

Most of the traditional attosecond pulse retrieval algorithms are based on a so-called attosecond streak camera technique, in which the momentum of the electron is shifted by an amount depending on the relative time delay between the attosecond pulse and the streaking infrared pulse. Thus, temporal information of the attosecond pulse is encoded in the amount of momentum shift in the streaked photoelectron momentum spectrogram S(p, τ), where p is the momentum of the electron along the polarization direction and τ is the time delay. An iterative algorithm is then employed to reconstruct the attosecond pulse from the streaking spectrogram. …


Stripe Order, Impurities, And Symmetry Breaking In A Diluted Frustrated Magnet, Xuecheng Ye, Rajesh Narayanan, Thomas Vojta Jan 2022

Stripe Order, Impurities, And Symmetry Breaking In A Diluted Frustrated Magnet, Xuecheng Ye, Rajesh Narayanan, Thomas Vojta

Physics Faculty Research & Creative Works

We investigate the behavior of the frustrated J1-J2 Ising model on a square lattice under the influence of random dilution and spatial anisotropies. Spinless impurities generate a random-field type disorder for the spin-density wave (stripe) order parameter. These random fields destroy the long-range stripe order in the case of spatially isotropic interactions. Combining symmetry arguments, percolation theory, and large-scale Monte Carlo simulations, we demonstrate that arbitrarily weak spatial interaction anisotropies restore the stripe phase. More specifically, the transition temperature Tc into the stripe phase depends on the interaction anisotropy ΔJ via Tc∼1/|ln(ΔJ)| for small …


Proton Radius: A Puzzle Or A Solution!?, Ulrich D. Jentschura Jan 2022

Proton Radius: A Puzzle Or A Solution!?, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

The proton radius puzzle is known as the discrepancy of the proton radius, obtained from muonic hydrogen spectroscopy (obtained as being roughly equal to 0.84 fm), and the proton radius obtained from (ordinary) hydrogen spectroscopy where a number of measurements involving highly excited states have traditionally favored a value of about 0.88 fm. Recently, a number of measurements of hydrogen transitions by the Munich (Garching) groups (notably, several hyperfine-resolved sublevels of the 2S-4P) and by the group at the University of Toronto (2S-2P 1/2) have led to transition frequency data consistent with the smaller proton radius of about 0.84 fm. …