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Physics Faculty Research & Creative Works

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Articles 151 - 180 of 1762

Full-Text Articles in Physical Sciences and Mathematics

Gw190412: Observation Of A Binary-Black-Hole Coalescence With Asymmetric Masses, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Aug 2020

Gw190412: Observation Of A Binary-Black-Hole Coalescence With Asymmetric Masses, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report the observation of gravitational waves from a binary-black-hole coalescence during the first two weeks of LIGO's and Virgo's third observing run. The signal was recorded on April 12, 2019 at 05:30:44 UTC with a network signal-to-noise ratio of 19. The binary is different from observations during the first two observing runs most notably due to its asymmetric masses: a ∼30 Mʘ black hole merged with a ∼8 Mʘ black hole companion. The more massive black hole rotated with a dimensionless spin magnitude between 0.22 and 0.60 (90% probability). Asymmetric systems are predicted to emit gravitational waves …

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Factorization Of High-Order-Harmonic-Generation Yields In Impurity-Doped Materials, Van Hung Hoang, Anh-Thu Le Aug 2020

Factorization Of High-Order-Harmonic-Generation Yields In Impurity-Doped Materials, Van Hung Hoang, Anh-Thu Le

Physics Faculty Research & Creative Works

We present a theoretical investigation of high-order-harmonic generation (HHG) from impurity-doped materials. Based on the analysis of the exact numerical solutions of the time-dependent Schrödinger equation (TDSE) for one-dimensional models, we demonstrate the factorization of HHG yields as a product of an electron wave packet and the recombination cross section, in analogy to HHG from atoms and molecules in the gas phase. Furthermore, we show that the quantitative rescattering model based on this factorization accurately reproduces the TDSE results. This opens up new possibilities to study impurities in materials using the available techniques from strong-field physics.

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Observation And Analysis Of Multiple Dark-Antidark Solitons In Two-Component Bose-Einstein Condensates, Garyfallia Katsimiga, Simeon I. Mistakidis, T. M. Bersano, M. K.H. Ome, S. M. Mossman, K. Mukherjee, P. Schmelcher, P. Engels, P. G. Kevrekidis Aug 2020

Observation And Analysis Of Multiple Dark-Antidark Solitons In Two-Component Bose-Einstein Condensates, Garyfallia Katsimiga, Simeon I. Mistakidis, T. M. Bersano, M. K.H. Ome, S. M. Mossman, K. Mukherjee, P. Schmelcher, P. Engels, P. G. Kevrekidis

Physics Faculty Research & Creative Works

We Report On The Static And Dynamical Properties Of Multiple Dark-Antidark Solitons (DADs) In Two-Component, Repulsively Interacting Bose-Einstein Condensates. Motivated By Experimental Observations Involving Multiple DADs, We Present A Theoretical Study Which Showcases That Bound States Consisting Of Dark (Antidark) Solitons In The First (Second) Component Of The Mixture Exist For Different Values Of Interspecies Interactions. It Is Found That Ensembles Of Few DADs May Exist As Stable Configurations, While For Larger DAD Arrays, The Relevant Windows Of Stability With Respect To The Interspecies Interaction Strength Become Progressively Narrower. Moreover, The Dynamical Formation Of States Consisting Of Alternating DADs In …

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Doping A Lattice-Trapped Bosonic Species With Impurities: From Ground State Properties To Correlated Tunneling Dynamics, Kevin Keiler, Simeon I. Mistakidis, Peter Schmelcher Aug 2020

Doping A Lattice-Trapped Bosonic Species With Impurities: From Ground State Properties To Correlated Tunneling Dynamics, Kevin Keiler, Simeon I. Mistakidis, Peter Schmelcher

Physics Faculty Research & Creative Works

We Investigate The Ground State Properties And The Nonequilibrium Dynamics Of A Lattice Trapped Bosonic Mixture Consisting Of An Impurity Species And A Finite-Sized Medium. For The Case Of One As Well As Two Impurities We Observe That, Depending On The Lattice Depth And The Interspecies Interaction Strength, A Transition From A Strongly Delocalized To A Localized Impurity Distribution Occurs. In The Latter Regime The Two Species Phase Separate, Thereby Forming A Particle-Hole Pair. For Two Impurities We Find That Below A Critical Lattice Depth They Are Delocalized Among Two Neighboring Outer Lattice Wells And Are Two-Body Correlated. This Transition …

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Robust Control Of The Minima Of High-Order Harmonics By Fine-Tuning The Alignment Of Co₂ Molecules For Shaping Attosecond Pulses And Probing Molecular Alignment, Cheng Jin, Su Ju Wang, Song Feng Zhao, Anh-Thu Le, C. D. Lin Jul 2020

Robust Control Of The Minima Of High-Order Harmonics By Fine-Tuning The Alignment Of Co₂ Molecules For Shaping Attosecond Pulses And Probing Molecular Alignment, Cheng Jin, Su Ju Wang, Song Feng Zhao, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

In a recent paper [C. Jin, S.-J. Wang, X. Zhao, S.-F. Zhao, and C. D. Lin, Phys. Rev. A 101, 013429 (2020)2469-992610.1103/PhysRevA.101.013429], we reported that the position and depth of the minima in the harmonic spectra of CO2 molecules can be dramatically manipulated by a slight change of the degree of alignment, thus providing a convenient method of shaping attosecond pulses which could lead to the splitting of a typical single attosecond burst into two. Here, we demonstrate that harmonic minima can also be dramatically controlled by changing the pump-probe angles to shape attosecond pulses. In the meanwhile, since …

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Collective Modes At A Disordered Quantum Phase Transition, Martin Puschmann, Jack Crewse, Jose A. Hoyos, Thomas Vojta Jul 2020

Collective Modes At A Disordered Quantum Phase Transition, Martin Puschmann, Jack Crewse, Jose A. Hoyos, Thomas Vojta

Physics Faculty Research & Creative Works

We study the collective excitations, i.e., the Goldstone (phase) mode and the Higgs (amplitude) mode, near the superfluid-Mott glass quantum phase transition in a two-dimensional system of disordered bosons. Using Monte Carlo simulations as well as an inhomogeneous quantum mean-field theory with Gaussian fluctuations, we show that the Higgs mode is strongly localized for all energies, leading to a noncritical scalar response. In contrast, the lowest-energy Goldstone mode undergoes a striking delocalization transition as the system enters the superfluid phase. We discuss the generality of these findings and experimental consequences, and we point out potential relations to many-body localization.

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Stationary And Dynamical Properties Of Two Harmonically Trapped Bosons In The Crossover From Two Dimensions To One, G. Bougas, Simeon I. Mistakidis, G. M. Alshalan, P. Schmelcher Jul 2020

Stationary And Dynamical Properties Of Two Harmonically Trapped Bosons In The Crossover From Two Dimensions To One, G. Bougas, Simeon I. Mistakidis, G. M. Alshalan, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Stationary Properties And The Interaction Quench Dynamics Of Two Bosons, Confined In A Two-Dimensional Anisotropic Harmonic Trap. A Transcendental Equation Is Derived Giving Access To The Energy Spectrum And Revealing The Dependence Of The Energy Gaps On The Anisotropy Parameter. The Relation Between The Two- And One-Dimensional Scattering Lengths As Well As The Tan Contacts Is Established. The Contact, Capturing The Two-Body Short-Range Correlations, Shows An Increasing Tendency For A Larger Anisotropy. Subsequently, The Interaction Quench Dynamics From Attractive To Repulsive Values And Vice Versa Is Investigated For Various Anisotropies. A Closed Analytical Form Of The Expansion …

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Many-Body Effects On Second-Order Phase Transitions In Spinor Bose-Einstein Condensates And Breathing Dynamics, K. M. Mittal, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher Jul 2020

Many-Body Effects On Second-Order Phase Transitions In Spinor Bose-Einstein Condensates And Breathing Dynamics, K. M. Mittal, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Correlation Effects Of The Second-Order Quantum Phase Transitions Emerging On The Ground State Of A Harmonically Trapped Spin-1 Bose Gas, Upon Varying The Involved Zeeman Terms, As Well As Its Breathing Dynamics Triggered By Quenching The Trapping Frequency. It Is Found That The Boundaries Of The Associated Magnetic Phases Are Altered In The Presence Of Interparticle Correlations For Both Ferromagnetic And Antiferromagnetic Spin-Spin Interactions, An Effect Which Becomes More Prominent In The Few-Body Scenario. Most Importantly, We Unveil A Correlation-Induced Shrinking Of The Antiferromagnetic And Broken-Axisymmetry Phases Implying That Ground States With Bosons Polarized In A Single …

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Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta Jun 2020

Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta

Physics Faculty Research & Creative Works

All vertebrate brains contain a dense matrix of thin fibers that release serotonin (5-hydroxytryptamine), a neurotransmitter that modulates a wide range of neural, glial, and vascular processes. Perturbations in the density of this matrix have been associated with a number of mental disorders, including autism and depression, but its self-organization and plasticity remain poorly understood. We introduce a model based on reflected Fractional Brownian Motion (FBM), a rigorously defined stochastic process, and show that it recapitulates some key features of regional serotonergic fiber densities. Specifically, we use supercomputing simulations to model fibers as FBM-paths in two-dimensional brain-like domains and demonstrate …

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Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website. Jun 2020

Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

A state of matter with a multi-component order parameter can give rise to vestigial order. In the vestigial phase, the primary order is only partially melted, leaving a remaining symmetry breaking behind, an effect driven by strong classical or quantum fluctuations. Vestigial states due to primary spin and charge-density-wave order have been discussed in iron-based and cuprate materials. Here we present the observation of a partially melted superconductivity in which pairing fluctuations condense at a separate phase transition and form a nematic state with broken Z3, i.e., three-state Potts-model symmetry. Thermal expansion, specific heat and magnetization measurements of …

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Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin Jun 2020

Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin

Physics Faculty Research & Creative Works

For a long time, the predictive limits of perturbative quantum field theory have been limited by our inability to carry out loop calculations to an arbitrarily high order, which become increasingly complex as the order of perturbation theory is increased. This problem is exacerbated by the fact that perturbation series derived from loop diagram (Feynman diagram) calculations represent asymptotic (divergent) series which limits the predictive power of perturbative quantum field theory. Here, we discuss an ansatz that could overcome these limits, based on the observations that (i) for many phenomenologically relevant field theories, one can derive dispersion relations which relate …

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Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura Jun 2020

Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Two recent experimental observations at the ATOMKI Institute of the Hungarian Academy of Sciences (regarding the angular emission pattern of electron-positron pairs from nuclear transitions from excited states in 8Be and 4He) indicate the possible existence of a particle of a rest mass energy of roughly 17 MeV. The so-called X17 particle constitutes a virtual state in the process, preceding the emission of the electron-positron pair. Based on the symmetry of the nuclear transitions (1+ → 0+ and 0- →0 +), the X17 could either be a vector, or a pseudoscalar particle. Here, we …

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Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher Jun 2020

Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Explore The Stability Of The Phase Separation Phenomenon In Few-Fermion Spin-1/2 Systems Confined In A Double-Well Potential. It Is Shown That Within The SU(2) Symmetric Case, Where The Total Spin Is Conserved, The Phase Separation Cannot Be Fully Stabilized. An Interaction Regime Characterized By Metastable Phase Separation Emerges For Intermediate Interactions Which Is Inherently Related With Ferromagnetic Spin-Spin Correlations Emerging Within Each Of The Wells. The Breaking Of The SU(2) Symmetry Crucially Affects The Stability Properties Of The System As The Phase Separated State Can Be Stabilized Even For Weak Magnetic Potential Gradients. Our Results Imply An Intricate Relation …

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Induced Correlations Between Impurities In A One-Dimensional Quenched Bose Gas, Simeon I. Mistakidis, A. G. Volosniev, P. Schmelcher May 2020

Induced Correlations Between Impurities In A One-Dimensional Quenched Bose Gas, Simeon I. Mistakidis, A. G. Volosniev, P. Schmelcher

Physics Faculty Research & Creative Works

We Explore The Time Evolution Of Two Impurities In A Trapped One-Dimensional Bose Gas That Follows A Change Of The Boson-Impurity Interaction. We Study The Induced Impurity-Impurity Interactions And Their Effect On The Quench Dynamics. In Particular, We Report On The Size Of The Impurity Cloud, The Impurity-Impurity Entanglement, And The Impurity-Impurity Correlation Function. The Presented Numerical Simulations Are Based Upon The Variational Multilayer Multiconfiguration Time-Dependent Hartree Method For Bosons. To Analyze And Quantify Induced Impurity-Impurity Correlations, We Employ An Effective Two-Body Hamiltonian With A Contact Interaction. We Show That The Effective Model Consistent With The Mean-Field Attraction Of Two …

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Origin Of High Carrier Concentration In Amorphous Wide-Bandgap Oxides: Role Of Disorder In Defect Formation And Electron Localization In In₂O₃₋​ₓ, Julia E. Medvedeva, I. A. Zhuravlev, C. Burris, D. B. Buchholz, M. Grayson, R. P. H. Chang May 2020

Origin Of High Carrier Concentration In Amorphous Wide-Bandgap Oxides: Role Of Disorder In Defect Formation And Electron Localization In In₂O₃₋​ₓ, Julia E. Medvedeva, I. A. Zhuravlev, C. Burris, D. B. Buchholz, M. Grayson, R. P. H. Chang

Physics Faculty Research & Creative Works

Structural disorder has been known to suppress carrier concentration and carrier mobility in common covalent semiconductors, such as silicon, by orders of magnitude. This is expected from a reduced overlap of the electron clouds on neighboring orbitals and the formation of localized tail states near the band edges caused by local distortions and lack of periodicity in the amorphous phase. In striking contrast to the covalent semiconductors, wide-bandgap oxides of post-transition metals with ionic bonding not only allow for crystalline-like electron mobility upon amorphization, but also exhibit two orders of magnitude higher carrier concentration in the disordered phase as compared …

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Correlated Dynamics Of Fermionic Impurities Induced By The Counterflow Of An Ensemble Of Fermions, J. Kwasniok, Simeon I. Mistakidis, P. Schmelcher May 2020

Correlated Dynamics Of Fermionic Impurities Induced By The Counterflow Of An Ensemble Of Fermions, J. Kwasniok, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Investigate The Nonequilibrium Quantum Dynamics Of One And Two Heavy Fermionic Impurities Being Harmonically Trapped And Repulsively Interacting With A Finite Ensemble Of Majority Fermions. A Quench Of The Potential Of The Majority Species From A Double-Well To A Harmonic Trap Is Applied, Enforcing Its Counterflow, Which In Turn Perturbs The Impurities. For Weak Repulsions, It Is Shown That The Mixture Undergoes A Periodic Mixing And Demixing Dynamics, While Stronger Interactions Lead To A More Pronounced Dynamical Spatial Separation. In The Presence Of Correlations, The Impurity Exhibits An Expansion Dynamics Which Is Absent In The Hartree-Fock Case, Resulting In …

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Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, Download The Pdf. Apr 2020

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, Download The Pdf.

Physics Faculty Research & Creative Works

We present the results from a search for gravitational-wave transients associated with core-collapse supernovae observed within a source distance of approximately 20 Mpc during the first and second observing runs of Advanced LIGO and Advanced Virgo. No significant gravitational-wave candidate was detected. We report the detection efficiencies as a function of the distance for waveforms derived from multidimensional numerical simulations and phenomenological extreme emission models. The sources with neutrino-driven explosions are detectable at the distances approaching 5 kpc, and for magnetorotationally driven explosions the distances are up to 54 kpc. However, waveforms for extreme emission models are detectable up to …

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Many-Body Quantum Dynamics And Induced Correlations Of Bose Polarons, Simeon I. Mistakidis, G. M. Koutentakis, Garyfallia Katsimiga, Th Busch, P. Schmelcher Apr 2020

Many-Body Quantum Dynamics And Induced Correlations Of Bose Polarons, Simeon I. Mistakidis, G. M. Koutentakis, Garyfallia Katsimiga, Th Busch, P. Schmelcher

Physics Faculty Research & Creative Works

We Study The Ground State Properties And Non-Equilibrium Dynamics Of Two Spinor Bosonic Impurities Immersed In A One-Dimensional Bosonic Gas Upon Applying An Interspecies Interaction Quench. For The Ground State Of Two Non-Interacting Impurities We Reveal Signatures Of Attractive Induced Interactions In Both Cases Of Attractive Or Repulsive Interspecies Interactions, While A Weak Impurity-Impurity Repulsion Forces The Impurities To Stay Apart. Turning To The Quench Dynamics We Inspect The Time-Evolution Of The Contrast Unveiling The Existence, Dynamical Deformation And The Orthogonality Catastrophe Of Bose Polarons. We Find That For An Increasing Postquench Repulsion The Impurities Reside In A Superposition Of …

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Quantum Interference Of K Capture In Energetic G E31+(1s)-Kr Collisions, R. Schuch, Michael Schulz, For Full List Of Authors, See Publisher's Website. Apr 2020

Quantum Interference Of K Capture In Energetic G E31+(1s)-Kr Collisions, R. Schuch, Michael Schulz, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We have measured characteristic K x rays in coincidence with the scattered particles from collisions of hydrogenlike Ge ions with Kr atoms. The ions were first accelerated to 8.6 MeV/amu, post-stripped to H-like charge state, and decelerated to around 2.5 MeV/amu. From the measurements the probabilities for K-shell to K-shell charge transfer as a function of collision impact parameters were obtained. The probabilities show an onset of oscillations which are interpreted as quantum interference between the K-shell to K-shell electron transfer amplitudes in two spatially separated coupling regions in the incoming and outgoing parts of the collision. The probabilities of …

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Enhancement And Reentrance Of Spin Triplet Superconductivity In Ute₂ Under Pressure, Sheng Ran, Hyunsoo Kim, I. Lin Liu, Shanta R. Saha, Ian Hayes, Tristin Metz, Yun Suk Eo, Johnpierre Paglione, Nicholas P. Butch Apr 2020

Enhancement And Reentrance Of Spin Triplet Superconductivity In Ute₂ Under Pressure, Sheng Ran, Hyunsoo Kim, I. Lin Liu, Shanta R. Saha, Ian Hayes, Tristin Metz, Yun Suk Eo, Johnpierre Paglione, Nicholas P. Butch

Physics Faculty Research & Creative Works

Spin triplet superconductivity in the Kondo lattice UTe2 appears to be associated with spin fluctuations originating from incipient ferromagnetic order. Here we show clear evidence of twofold enhancement of superconductivity under pressure, which discontinuously transitions to magnetic order, likely of ferromagnetic nature, at higher pressures. The application of a magnetic field tunes the system back across a first-order phase boundary. Straddling this phase boundary, we find another example of reentrant superconductivity in UTe2. As the superconductivity and magnetism exist on two opposite sides of the first-order phase boundary, our results indicate other microscopic mechanisms may be playing …

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Differential Study Of Projectile Coherence Effects On Double Capture Processes In P + Ar Collisions, Trevor Voss, Basu R. Lamichhane, Madhav Dhital, Ramaz Lomsadze, Michael Schulz Mar 2020

Differential Study Of Projectile Coherence Effects On Double Capture Processes In P + Ar Collisions, Trevor Voss, Basu R. Lamichhane, Madhav Dhital, Ramaz Lomsadze, Michael Schulz

Physics Faculty Research & Creative Works

We have measured differential yields for double capture and double capture accompanied by ionization in 75 keV p + Ar collisions. Data were taken for two different transverse projectile coherence lengths. A small effect of the projectile coherence properties on the yields were found for double capture, but not for double capture plus ionization. The results suggest that multiple projectile-target interactions can lead to a significant weakening of projectile coherence effects.

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Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M O, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Mar 2020

Gw190425: Observation Of A Compact Binary Coalescence With Total Mass ∼ 3.4 M O, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

On 2019 April 25, the LIGO Livingston detector observed a compact binary coalescence with signal-to-noise ratio 12.9. The Virgo detector was also taking data that did not contribute to detection due to a low signal-to-noise ratio, but were used for subsequent parameter estimation. The 90% credible intervals for the component masses range from to if we restrict the dimensionless component spin magnitudes to be smaller than 0.05). These mass parameters are consistent with the individual binary components being neutron stars. However, both the source-frame chirp mass and the total mass of this system are significantly larger than those of any …

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Quench Induced Vortex-Bright-Soliton Formation In Binary Bose-Einstein Condensates, K. Mukherjee, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher Feb 2020

Quench Induced Vortex-Bright-Soliton Formation In Binary Bose-Einstein Condensates, K. Mukherjee, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Spontaneous Generation Of Vortex-Bright-Soliton Structures In Binary Bose-Einstein Condensates With A Small Mass Imbalance Between The Species Confined In A Two-Dimensional Harmonic Trap Where One Of The Two Species Has Been Segmented Into Two Parts By A Potential Barrier. To Trigger The Dynamics The Potential Barrier Is Suddenly Removed And Subsequently The Segments Perform A Counterflow Dynamics. We Consider A Relative Phase Difference Of Π Between The Segments, While A Singly Quantized Vortex May Be Imprinted At The Center Of The Other Species. The Number Of Vortex Structures Developed Within The Segmented Species Following The Merging Of …

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Pulse- And Continuously Driven Many-Body Quantum Dynamics Of Bosonic Impurities In A Bose-Einstein Condensate, K. Mukherjee, Simeon I. Mistakidis, S. Majumder, P. Schmelcher Feb 2020

Pulse- And Continuously Driven Many-Body Quantum Dynamics Of Bosonic Impurities In A Bose-Einstein Condensate, K. Mukherjee, Simeon I. Mistakidis, S. Majumder, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Periodically Driven Dynamics Of Two Repulsively Interacting Bosonic Impurities Within A Bosonic Bath Upon Considering Either The Impact Of A Finite Pulse Or Continuous Shaking Of The Impurities Harmonic Trap. Following A Pulse Driving Of Initially Miscible Components, We Reveal A Variety Of Dynamical Response Regimes Depending On The Driving Frequency. At Resonant Drivings, The Impurities Decouple From Their Host, While If Exposed To A High-Frequency Driving, They Remain Trapped In The Bosonic Gas. For Continuous Shaking, We Showcase That In The Resonantly Driven Regime The Impurities Oscillate Back And Forth Within And Outside The Bosonic Medium. …

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Model Comparison From Ligo-Virgo Data On Gw170817'S Binary Components And Consequences For The Merger Remnant, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jan 2020

Model Comparison From Ligo-Virgo Data On Gw170817'S Binary Components And Consequences For The Merger Remnant, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

GW170817 is the very first observation of gravitational waves originating from the coalescence of two compact objects in the mass range of neutron stars, accompanied by electromagnetic counterparts, and offers an opportunity to directly probe the internal structure of neutron stars. We perform Bayesian model selection on a wide range of theoretical predictions for the neutron star equation of state. For the binary neutron star hypothesis, we find that we cannot rule out the majority of theoretical models considered. In addition, the gravitational-wave data alone does not rule out the possibility that one or both objects were low-mass black holes. …

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Entanglement-Assisted Tunneling Dynamics Of Impurities In A Double Well Immersed In A Bath Of Lattice Trapped Bosons, Friethjof Theel, Kevin Keiler, Simeon I. Mistakidis, Peter Schmelcher Jan 2020

Entanglement-Assisted Tunneling Dynamics Of Impurities In A Double Well Immersed In A Bath Of Lattice Trapped Bosons, Friethjof Theel, Kevin Keiler, Simeon I. Mistakidis, Peter Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Correlated Tunneling Dynamics Of An Impurity Trapped In A Double Well And Interacting Repulsively With A Majority Species Of Lattice Trapped Bosons. Upon Quenching The Tilt Of The Double Well It Is Found That The Quench-Induced Tunneling Dynamics Depends Crucially On The Interspecies Interaction Strength And The Presence Of Entanglement Inherent In The System. In Particular, For Weak Couplings The Impurity Performs A Rather Irregular Tunneling Process In The Double Well. Increasing The Interspecies Coupling It Is Possible To Control The Response Of The Impurity Which Undergoes A Delayed Tunneling While The Majority Species Effectively Acts As …

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Search For Gravitational Waves From Scorpius X-1 In The Second Advanced Ligo Observing Run With An Improved Hidden Markov Model, B. P. Abbott, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Dec 2019

Search For Gravitational Waves From Scorpius X-1 In The Second Advanced Ligo Observing Run With An Improved Hidden Markov Model, B. P. Abbott, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095% = …

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Local Orbital Degeneracy Lifting As A Precursor To An Orbital-Selective Peierls Transition, E. S. Bozin, W. G. Yin, R. J. Koch, M. Abeykoon, Yew San Hor, H. Zheng, H. C. Lei, C. Petrovic, J. F. Mitchell, S. J. L. Billinge Dec 2019

Local Orbital Degeneracy Lifting As A Precursor To An Orbital-Selective Peierls Transition, E. S. Bozin, W. G. Yin, R. J. Koch, M. Abeykoon, Yew San Hor, H. Zheng, H. C. Lei, C. Petrovic, J. F. Mitchell, S. J. L. Billinge

Physics Faculty Research & Creative Works

Fundamental electronic principles underlying all transition metal compounds are the symmetry and filling of the d-electron orbitals and the influence of this filling on structural configurations and responses. Here we use a sensitive local structural technique, x-ray atomic pair distribution function analysis, to reveal the presence of fluctuating local-structural distortions at high temperature in one such compound, CuIr2S4. We show that this hitherto overlooked fluctuating symmetry-lowering is electronic in origin and will modify the energy-level spectrum and electronic and magnetic properties. The explanation is a local, fluctuating, orbital-degeneracy-lifted state. The natural extension of our result would …

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Lattice Thermal Conductivity Of Quartz At High Pressure And Temperature From The Boltzmann Transport Equation, Xue Xiong, Eugene J. Ragasa, Aleksandr V. Chernatynskiy, Dawei Tang, Simon R. Phillpot Dec 2019

Lattice Thermal Conductivity Of Quartz At High Pressure And Temperature From The Boltzmann Transport Equation, Xue Xiong, Eugene J. Ragasa, Aleksandr V. Chernatynskiy, Dawei Tang, Simon R. Phillpot

Physics Faculty Research & Creative Works

The thermal conductivities along the basal and hexagonal directions of α-quartz silica, the low-temperature form of crystalline SiO2, are predicted from the solution of the Boltzmann transport equation combined with the van Beest, Kramer, and van Santen potential for the temperature up to 900 K and the pressure as high as 4 GPa. The thermal conductivities at atmospheric pressure, which show a negative and nonlinear dependence on temperature, are in reasonable agreement with the experimental data. The influence of pressure on thermal conductivity is positive and linear. The pressure (P) and temperature (T) dependences of the thermal conductivity …

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The Conundrum Of Relaxation Volumes In First-Principles Calculations Of Charged Defects In Uo₂, Anuj Goyal, Kiran Mathew, Richard G. Hennig, Aleksandr V. Chernatynskiy Dec 2019

The Conundrum Of Relaxation Volumes In First-Principles Calculations Of Charged Defects In Uo₂, Anuj Goyal, Kiran Mathew, Richard G. Hennig, Aleksandr V. Chernatynskiy

Physics Faculty Research & Creative Works

The defect relaxation volumes obtained from density-functional theory (DFT) calculations of charged vacancies and interstitials are much larger than their neutral counterparts, seemingly unphysically large. We focus on UO2 as our primary material of interest, but also consider Si and GaAs to reveal the generality of our results. In this work, we investigate the possible reasons for this and revisit the methods that address the calculation of charged defects in periodic DFT. We probe the dependence of the proposed energy corrections to charged defect formation energies on relaxation volumes and find that corrections such as potential alignment remain ambiguous with …

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