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Articles 1321 - 1350 of 6056

Full-Text Articles in Physical Sciences and Mathematics

Electron-Impact Ionization Of Laser-Aligned Atoms -- Contributions From Both Natural And Unnatural-Parity States, Andrew James Murray, James Colgan, Don H. Madison, Matthew Harvey, Ahmad Sakaamini Aug 2017

Electron-Impact Ionization Of Laser-Aligned Atoms -- Contributions From Both Natural And Unnatural-Parity States, Andrew James Murray, James Colgan, Don H. Madison, Matthew Harvey, Ahmad Sakaamini

Physics Faculty Research & Creative Works

Synopsis. The progress of experimental and theoretical measurements for (e,2e) ionization cross sections from laser-aligned atoms is presented here. It is found that both natural and unnatural parity contributions must be included in the models to emulate the experimental data.

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Inverse Design Of Perfectly Transmitting Eigenchannels In Scattering Media, Milan Koirala, Raktim Sarma, Hui Cao, Alexey Yamilov Aug 2017

Inverse Design Of Perfectly Transmitting Eigenchannels In Scattering Media, Milan Koirala, Raktim Sarma, Hui Cao, Alexey Yamilov

Physics Faculty Research & Creative Works

Light-matter interactions inside a turbid medium can be controlled by tailoring the spatial distribution of energy density throughout the system. Wavefront shaping allows selective coupling of incident light to different transmission eigenchannels, producing dramatically different spatial intensity profiles. In contrast to the density of transmission eigenvalues that is dictated by the universal bimodal distribution, the spatial structures of the eigenchannels are not universal and depend on the confinement geometry of the system. Here, we develop and verify a model for the transmission eigenchannel with the corresponding eigenvalue close to unity. By projecting the original problem of two-dimensional diffusion in a …

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Magnetic Control Of Lateral Migration Of Ellipsoidal Microparticles In Microscale Flows, R. Zhou, C. A. Sobecki, J. Zhang, Yanzhi Zhang, Cheng Wang Aug 2017

Magnetic Control Of Lateral Migration Of Ellipsoidal Microparticles In Microscale Flows, R. Zhou, C. A. Sobecki, J. Zhang, Yanzhi Zhang, Cheng Wang

Mathematics and Statistics Faculty Research & Creative Works

No abstract provided.

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(E,2e) Ionization Studies Of N₂ At Low To Intermediate Energies From A Coplanar Geometry To The Perpendicular Plane, Ahmad Sakaamini, Matthew Harvey, Sadek Amami, Andrew James Murray, Don H. Madison, Chuangang Ning Aug 2017

(E,2e) Ionization Studies Of N₂ At Low To Intermediate Energies From A Coplanar Geometry To The Perpendicular Plane, Ahmad Sakaamini, Matthew Harvey, Sadek Amami, Andrew James Murray, Don H. Madison, Chuangang Ning

Physics Faculty Research & Creative Works

Synopsis. The progress of experimental and theoretical measurements for (e,2e) ionization cross sections from Nitrogen molecules is presented. Results are given for energies from ~10 eV above the ionization potential (IP) through to ~100 eV above the IP for the 3σg, 1πu and 2σg states.

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A Unified Ab Initio Approach To The Correlated Quantum Dynamics Of Ultracold Fermionic And Bosonic Mixtures, L. Cao, V. Bolsinger, Simeon I. Mistakidis, G. M. Koutentakis, S. Krönke, J. M. Schurer, P. Schmelcher Jul 2017

A Unified Ab Initio Approach To The Correlated Quantum Dynamics Of Ultracold Fermionic And Bosonic Mixtures, L. Cao, V. Bolsinger, Simeon I. Mistakidis, G. M. Koutentakis, S. Krönke, J. M. Schurer, P. Schmelcher

Physics Faculty Research & Creative Works

We Extent The Recently Developed Multi-Layer Multi-Configuration Time-Dependent Hartree Method For Bosons For Simulating The Correlated Quantum Dynamics Of Bosonic Mixtures To The Fermionic Sector And Establish A Unifying Approach For The Investigation Of The Correlated Quantum Dynamics Of A Mixture Of Indistinguishable Particles, Be It Fermions Or Bosons. Relying On A Multi-Layer Wave-Function Expansion, The Resulting Multi-Layer Multi-Configuration Time-Dependent Hartree Method For Mixtures (ML-MCTDHX) Can Be Adapted To Efficiently Resolve System-Specific Intra- And Inter-Species Correlations. The Versatility And Efficiency Of ML-MCTDHX Are Demonstrated By Applying It To The Problem Of Colliding Few-Atom Mixtures Of Both Bose-Fermi And Fermi-Fermi Types. …

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Evaluation Of Deep Learning Frameworks Over Different Hpc Architectures, Shayan Shams, Richard Platania, Kisung Lee, Seung Jong Park Jul 2017

Evaluation Of Deep Learning Frameworks Over Different Hpc Architectures, Shayan Shams, Richard Platania, Kisung Lee, Seung Jong Park

Computer Science Faculty Research & Creative Works

Recent advances in deep learning have enabled researchers across many disciplines to uncover new insights about large datasets. Deep neural networks have shown applicability to image, time-series, textual, and other data, all of which are available in a plethora of research fields. However, their computational complexity and large memory overhead requires advanced software and hardware technologies to train neural networks in a reasonable amount of time. To make this possible, there has been an influx in development of deep learning software that aim to leverage advanced hardware resources. In order to better understand the performance implications of deep learning frameworks …

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Cnn Based 3d Facial Expression Recognition Using Masking And Landmark Features, Huiyuan Yang, Lijun Yin Jul 2017

Cnn Based 3d Facial Expression Recognition Using Masking And Landmark Features, Huiyuan Yang, Lijun Yin

Computer Science Faculty Research & Creative Works

Automatically recognizing facial expression is an important part for human-machine interaction. In this paper, we first review the previous studies on both 2D and 3D facial expression recognition, and then summarize the key research questions to solve in the future. Finally, we propose a 3D facial expression recognition (FER) algorithm using convolutional neural networks (CNNs) and landmark features/masks, which is invariant to pose and illumination variations due to the solely use of 3D geometric facial models without any texture information. The proposed method has been tested on two public 3D facial expression databases: BU-4DFE and BU-3DFE. The results show that …

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Quantum Percolation Phase Transition And Magnetoelectric Dipole Glass In Hexagonal Ferrites, S. E. Rowley, Thomas Vojta, A. T. Jones, W. Guo, J. Oliveira, For Full List Of Authors, See Publisher's Website. Jul 2017

Quantum Percolation Phase Transition And Magnetoelectric Dipole Glass In Hexagonal Ferrites, S. E. Rowley, Thomas Vojta, A. T. Jones, W. Guo, J. Oliveira, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Hexagonal ferrites not only have enormous commercial impact (£2 billion/year in sales) due to applications that include ultrahigh-density memories, credit-card stripes, magnetic bar codes, small motors, and low-loss microwave devices, they also have fascinating magnetic and ferroelectric quantum properties at low temperatures. Here we report the results of tuning the magnetic ordering temperature in PbFe12-xGaxO19 to zero by chemical substitution x. The phase transition boundary is found to vary as TN ∼ (1-x/xc)2/3 with xc very close to the calculated spin percolation threshold, which we determine by Monte Carlo simulations, …

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Search For High-Energy Neutrinos From Gravitational Wave Event Gw151226 And Candidate Lvt151012 With Antares And Icecube, A. Albert, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jul 2017

Search For High-Energy Neutrinos From Gravitational Wave Event Gw151226 And Candidate Lvt151012 With Antares And Icecube, A. Albert, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The Advanced LIGO observatories detected gravitational waves from two binary black hole mergers during their first observation run (O1). We present a high-energy neutrino follow-up search for the second gravitational wave event, GW151226, as well as for gravitational wave candidate LVT151012. We find two and four neutrino candidates detected by IceCube, and one and zero detected by Antares, within ±500 s around the respective gravitational wave signals, consistent with the expected background rate. None of these neutrino candidates are found to be directionally coincident with GW151226 or LVT151012. We use nondetection to constrain isotropic-equivalent high-energy neutrino emission from GW151226, adopting …

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Mantle Transition Zone Discontinuities Beneath The Indochina Peninsula: Implications For Slab Subduction And Mantle Upwelling, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanhphon Le Jul 2017

Mantle Transition Zone Discontinuities Beneath The Indochina Peninsula: Implications For Slab Subduction And Mantle Upwelling, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanhphon Le

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

While the northward indentation of the Indian into Eurasian plates has been intensively investigated, its oblique subduction beneath the Indochina Peninsula (ICP) and the role it played on mantle structure and dynamics remain enigmatic. In this first regional-scale receiver function study of the mantle transition zone (MTZ) discontinuities beneath the ICP and its surrounding areas, we stack ~12,000 receiver functions recorded at 33 stations using a non-plane wave common-conversion-point stacking technique. Systematic spatial variations of MTZ thickness with departures between -21 and +24 km from the globally averaged value are revealed, providing independent evidence for the presence of slab segments …

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Homogenization Of Plastic Deformation In Heterogeneous Lamella Structures, Rui Yuan, Irene J. Beyerlein, Caizhi Zhou Jul 2017

Homogenization Of Plastic Deformation In Heterogeneous Lamella Structures, Rui Yuan, Irene J. Beyerlein, Caizhi Zhou

Materials Science and Engineering Faculty Research & Creative Works

It has been shown that unlike its constituent nanocrystalline (NC) phase, a heterogeneous lamella (HL) composite comprising NC and coarse-grain layers exhibits greatly improved ductility. To understand the origin of this enhancement, we present a 3D discrete dislocation, crystal plasticity finite element model to study the development of strains across this microstructure. Here we show that the HL structure homogenizes the plastic strains in the NC layer, weakening the effect of strain concentrations. These findings can provide valuable insight into the effects of material length scales on material instabilities, which is needed to design heterogeneous structures with superior properties.

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Fuzzy Color Clustering For Melanoma Diagnosis In Dermoscopy Images, Haidar A. Almubarak, R. Joe Stanley, William V. Stoecker, Randy Hays Moss Jul 2017

Fuzzy Color Clustering For Melanoma Diagnosis In Dermoscopy Images, Haidar A. Almubarak, R. Joe Stanley, William V. Stoecker, Randy Hays Moss

Electrical and Computer Engineering Faculty Research & Creative Works

A fuzzy logic-based color histogram analysis technique is presented for discriminating benign skin lesions from malignant melanomas in dermoscopy images. The approach extends previous research for utilizing a fuzzy set for skin lesion color for a specified class of skin lesions, using alpha-cut and support set cardinality for quantifying a fuzzy ratio skin lesion color feature. Skin lesion discrimination results are reported for the fuzzy clustering ratio over different regions of the lesion over a data set of 517 dermoscopy images consisting of 175 invasive melanomas and 342 benign lesions. Experimental results show that the fuzzy clustering ratio applied over …

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Search For Intermediate Mass Black Hole Binaries In The First Observing Run Of Advanced Ligo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jul 2017

Search For Intermediate Mass Black Hole Binaries In The First Observing Run Of Advanced Ligo, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

During their first observational run, the two Advanced LIGO detectors attained an unprecedented sensitivity, resulting in the first direct detections of gravitational-wave signals produced by stellar-mass binary black hole systems. This paper reports on an all-sky search for gravitational waves (GWs) from merging intermediate mass black hole binaries (IMBHBs). The combined results from two independent search techniques were used in this study: the first employs a matched-filter algorithm that uses a bank of filters covering the GW signal parameter space, while the second is a generic search for GW transients (bursts). No GWs from IMBHBs were detected; therefore, we constrain …

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Seismic Anisotropy And Mantle Dynamics Beneath The Malawi Rift Zone, East Africa, Cory A. Reed, Kelly H. Liu, Youqiang Yu, Stephen S. Gao Jul 2017

Seismic Anisotropy And Mantle Dynamics Beneath The Malawi Rift Zone, East Africa, Cory A. Reed, Kelly H. Liu, Youqiang Yu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

SKS, SKKS, and PKS splitting parameters measured at 34 seismic stations that we deployed in the vicinity of the Cenozoic Malawi Rift Zone (MRZ) of the East African Rift System demonstrate systematic spatial variations with an average splitting time of 1.0 ± 0.3 s. The overall NE-SW fast orientations are consistent with absolute plate motion (APM) models of the African Plate constructed under the assumption of no-net rotation of the global lithosphere and are inconsistent with predicted APM directions from models employing a fixed hot spot reference frame. They also depart considerably from the trend of most of the major …

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Determination Of The Energy Band Gap Of Bi₂Se₃, G. Martinez, B. A. Piot, M. Hakl, M. Potemski, Yew San Hor Jul 2017

Determination Of The Energy Band Gap Of Bi₂Se₃, G. Martinez, B. A. Piot, M. Hakl, M. Potemski, Yew San Hor

Physics Faculty Research & Creative Works

Despite intensive investigations of Bi2Se3 in past few years, the size and nature of the bulk energy band gap of this well-known 3D topological insulator still remain unclear. Here we report on a combined magneto-transport, photoluminescence and infrared transmission study of Bi2Se3, which unambiguously shows that the energy band gap of this material is direct and reaches Eg = (220 ± 5) meV at low temperatures.

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Superfluid-Mott Glass Quantum Multicritical Point On A Percolating Lattice, Martin Puschmann, Thomas Vojta Jul 2017

Superfluid-Mott Glass Quantum Multicritical Point On A Percolating Lattice, Martin Puschmann, Thomas Vojta

Physics Faculty Research & Creative Works

We employ large-scale Monte Carlo simulations to study a particle-hole symmetric site-diluted quantum rotor model in two dimensions. The ground state phase diagram of this system features two distinct quantum phase transitions between the superuid and the insulating (Mott glass) phases. They are separated by a multicritical point. The generic transition for dilutions below the lattice percolation threshold is driven by quantum uctuations while thetransition across the percolation threshold is due to the geometric uctuations of the lattice. We determine the location of the multicritical point between these two transitions and find its critical behavior. The multicritical exponents read z …

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Dark-Bright Soliton Dynamics Beyond The Mean-Field Approximation, Garyfallia C. Katsimiga, G. M. Koutentakis, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher Jul 2017

Dark-Bright Soliton Dynamics Beyond The Mean-Field Approximation, Garyfallia C. Katsimiga, G. M. Koutentakis, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher

Physics Faculty Research & Creative Works

The Dynamics Of Dark-Bright (DB) Solitons Beyond The Mean-Field Approximation Is Investigated. We First Examine The Case Of A Single DB Soliton And Its Oscillations Within A Parabolic Trap. Subsequently, We Move To The Setting Of Collisions, Comparing The Mean-Field Approximation To That Involving Multiple Orbitals In Both The Dark And The Bright Component. Fragmentation Is Present And Significantly Affects The Dynamics, Especially In The Case Of Slower Solitons And In That Of Lower Atom Numbers. It Is Shown That The Presence Of Fragmentation Allows For Bipartite Entanglement Between The Distinguishable Species. Most Importantly The Interplay Between Fragmentation And Entanglement …

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Enhanced Coupling Of Light Into A Turbid Medium Through Microscopic Interface Engineering, Jonathan V. Thompson, Brett H. Hokr, Wihan Kim, Charles W. Ballmann, Brian E. Applegate, Javier Jo, Alexey Yamilov, Hui Cao, Marlan O. Scully, Vladislav V. Yakovlev Jul 2017

Enhanced Coupling Of Light Into A Turbid Medium Through Microscopic Interface Engineering, Jonathan V. Thompson, Brett H. Hokr, Wihan Kim, Charles W. Ballmann, Brian E. Applegate, Javier Jo, Alexey Yamilov, Hui Cao, Marlan O. Scully, Vladislav V. Yakovlev

Physics Faculty Research & Creative Works

There are many optical detection and sensing methods used today that provide powerful ways to diagnose, characterize, and study materials. For example, the measurement of spontaneous Raman scattering allows for remote detection and identification of chemicals. Many other optical techniques provide unique solutions to learn about biological, chemical, and even structural systems. However, when these systems exist in a highly scattering or turbid medium, the optical scattering effects reduce the effectiveness of these methods. In this article, we demonstrate a method to engineer the geometry of the optical interface of a turbid medium, thereby drastically enhancing the coupling efficiency of …

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Hypoelliptic Multiscale Langevin Diffusions: Large Deviations, Invariant Measures And Small Mass Asymptotics, Wenqing Hu, Konstantinos Spiliopoulosï Jun 2017

Hypoelliptic Multiscale Langevin Diffusions: Large Deviations, Invariant Measures And Small Mass Asymptotics, Wenqing Hu, Konstantinos Spiliopoulosï

Mathematics and Statistics Faculty Research & Creative Works

We consider a general class of hypoelliptic Langevin diffusions and study two related questions. The first question is large deviations for hypoelliptic multiscale diffusions as the noise and the scale separation parameter go to zero. The second question is small mass asymptotics of (a) the invariant measure corresponding to the hypoelliptic Langevin operator and of (b) related hypoelliptic Poisson equations. The invariant measure corresponding to the hypoelliptic problem and appropriate hypoelliptic Poisson equations enter the large deviations rate function due to the multiscale effects. Based on the small mass asymptotics we derive that the large deviations behavior of the multiscale …

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Natural Convection In Redox Electrochemistry: Model, Simulation And Experiments, Fangping Yuan, Kakkattukuzhy M. Isaac Jun 2017

Natural Convection In Redox Electrochemistry: Model, Simulation And Experiments, Fangping Yuan, Kakkattukuzhy M. Isaac

Collaborative Research: Actively Controllable Microfluidics with Film-Confined Redox-Magnetohydrodynamics -- Video and Data

No abstract provided.

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Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jun 2017

Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Results are presented from a semicoherent search for continuous gravitational waves from the brightest low-mass X-ray binary, Scorpius X-1, using data collected during the first Advanced LIGO observing run. The search combines a frequency domain matched filter (Bessel-weighted F-statistic) with a hidden Markov model to track wandering of the neutron star spin frequency. No evidence of gravitational waves is found in the frequency range 60-650 Hz. Frequentist 95% confidence strain upper limits, h095%=4.0 x 10-25, 8.3 x 10-25, and 3.0 x 10-25 for electromagnetically restricted source orientation, unknown polarization, and circular …

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Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus Jun 2017

Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Upper Mississippi Embayment (UME), where the seismically active New Madrid Seismic Zone resides, experienced two phases of subsidence commencing in the Late Precambrian and Cretaceous, respectively. To provide new constraints on models proposed for the mechanisms responsible for the subsidence, we computed and stacked P-to-S receiver functions recorded by 49 USArray and other seismic stations located in the UME and the adjacent Ozark Uplift and modeled Bouguer gravity anomaly data. The inferred thickness, density, and Vp/Vs of the upper and lower crustal layers suggest that the UME is characterized by a mafic and high-density upper crustal …

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Energy-Efficient Multi-Core Scheduling For Real-Time Dag Tasks, Zhishan Guo, Ashikahmed Bhuiyan, Abusayeed Saifullah, Nan Guan, Haoyi Xiong Jun 2017

Energy-Efficient Multi-Core Scheduling For Real-Time Dag Tasks, Zhishan Guo, Ashikahmed Bhuiyan, Abusayeed Saifullah, Nan Guan, Haoyi Xiong

Computer Science Faculty Research & Creative Works

In this work, we study energy-aware real-time scheduling of a set of sporadic Directed Acyclic Graph (DAG) tasks with implicit deadlines. While meeting all real-time constraints, we try to identify the best task allocation and execution pattern such that the average power consumption of the whole platform is minimized. To the best of our knowledge, this is the first work that addresses the power consumption issue in scheduling multiple DAG tasks on multi-cores and allows intra-task processor sharing. We first adapt the decomposition-based framework for federated scheduling and propose an energy-sub-optimal scheduler. Then we derive an approximation algorithm to identify …

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Lensing Is Low: Cosmology, Galaxy Formation Or New Physics?, Alexie Leauthaud, Shun Saito, For Full List Of Authors, See Publisher's Website. Jun 2017

Lensing Is Low: Cosmology, Galaxy Formation Or New Physics?, Alexie Leauthaud, Shun Saito, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We present high signal-to-noise galaxy-galaxy lensing measurements of the Baryon Oscillation Spectroscopic Survey constant mass (CMASS) sample using 250 deg2 of weak-lensing data from Canada-France-Hawaii Telescope Lensing Survey and Canada-France-Hawaii Telescope Stripe 82 Survey. We compare this signal with predictions from mock catalogues trained to match observables including the stellar mass function and the projected and twodimensional clustering of CMASS. We show that the clustering of CMASS, together with standard models of the galaxy-halo connection, robustly predicts a lensing signal that is 20-40 per cent larger than observed. Detailed tests show that our results are robust to a variety …

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Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jun 2017

Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10 11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2-6.0+8.4M⊙ and 19.4-5.9+5.3M⊙ (at the 90% credible level). The black hole spins are best constrained through measurement of the effective …

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Quantum Griffiths Phase Inside The Ferromagnetic Phase Of Ni₁₋ₓvₓ, Ruize Wang, Adane Gebretsadik, Sara Ubaid-Kassis, Almut Schroeder, Thomas Vojta, For Full List Of Authors, See Publisher's Website. Jun 2017

Quantum Griffiths Phase Inside The Ferromagnetic Phase Of Ni₁₋ₓvₓ, Ruize Wang, Adane Gebretsadik, Sara Ubaid-Kassis, Almut Schroeder, Thomas Vojta, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We study by means of bulk and local probes the d-metal alloy Ni1-xVx close to the quantum critical concentration, xc ≈ 11.6%, where the ferromagnetic transition temperature vanishes. The magnetization-field curve in the ferromagnetic phase takes an anomalous power-law form with a nonuniversal exponent that is strongly x dependent and mirrors the behavior in the paramagnetic phase. Muon spin rotation experiments demonstrate inhomogeneous magnetic order and indicate the presence of dynamic fluctuating magnetic clusters. These results provide strong evidence for a quantum Griffiths phase on the ferromagnetic side of the quantum phase transition.

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Quantum Dynamical Response Of Ultracold Few-Boson Ensembles In Finite Optical Lattices To Multiple Interaction Quenches, J. Neuhaus-Steinmetz, Simeon I. Mistakidis, P. Schmelcher May 2017

Quantum Dynamical Response Of Ultracold Few-Boson Ensembles In Finite Optical Lattices To Multiple Interaction Quenches, J. Neuhaus-Steinmetz, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

The Correlated Nonequilibrium Quantum Dynamics Following A Multiple Interaction Quench Protocol For Few-Bosonic Ensembles Confined In Finite Optical Lattices Is Investigated. The Quenches Give Rise To An Interwell Tunneling And Excite The Cradle And A Breathing Mode. Several Tunneling Pathways Open During The Time Interval Of Increased Interactions, While Only A Few Occur When The System Is Quenched Back To Its Original Interaction Strength. The Cradle Mode, However, Persists During And In Between The Quenches, While The Breathing Mode Possesses Distinct Frequencies. The Occupation Of Excited Bands Is Explored In Detail Revealing A Monotonic Behavior With Increasing Quench Amplitude And …

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Oscillation Criteria For Third-Order Nonlinear Functional Difference Equations With Damping, Martin Bohner, C. Dharuman, R. Srinivasan, Ethiraju Thandapani May 2017

Oscillation Criteria For Third-Order Nonlinear Functional Difference Equations With Damping, Martin Bohner, C. Dharuman, R. Srinivasan, Ethiraju Thandapani

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we obtain some new criteria for the oscillation of certain third-order difference equations using comparison principles with a suitable couple of first-order difference equations. The presented results improve and extend the earlier ones. Examples are provided to illustrate the main results.

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Role Of The Recoil Ion In Single-Electron Capture And Single-Ionization Processes For Collisions Of Protons With He And Ar Atoms, P. Focke, Ronald E. Olson, N. D. Cariatore, M. Alessi, S. Otranto May 2017

Role Of The Recoil Ion In Single-Electron Capture And Single-Ionization Processes For Collisions Of Protons With He And Ar Atoms, P. Focke, Ronald E. Olson, N. D. Cariatore, M. Alessi, S. Otranto

Physics Faculty Research & Creative Works

In this work the single-electron capture and single-ionization processes are studied for proton collisions with He and Ar atoms at impact energies in the range 25–100 keV. Classical trajectory Monte Carlo simulations are benchmarked against experimental data obtained at the reaction microscope in Bariloche, Argentina, which employs the cold target recoil-ion momentum spectroscopy technique. Special emphasis is placed on describing the momentum transfer to the recoil ion for these collision systems.

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The Covalent Interaction Between Dihydrogen And Gold: A Rotational Spectroscopic Study Of H₂-Aucl, Daniel A. Obenchain, Derek S. Frank, Garry S. Grubbs, Herbert M. Pickett, Stewart E. Novick May 2017

The Covalent Interaction Between Dihydrogen And Gold: A Rotational Spectroscopic Study Of H₂-Aucl, Daniel A. Obenchain, Derek S. Frank, Garry S. Grubbs, Herbert M. Pickett, Stewart E. Novick

Chemistry Faculty Research & Creative Works

The pure rotational transitions of H2-AuCl have been measured using a pulsed-jet cavity Fourier transform microwave spectrometer equipped with a laser ablation source. The structure was found to be T-shaped, with the H-H bond interacting with the gold atom. Both 35Cl and 37Cl isotopologues have been measured for both ortho and para states of H2. Rotational constants, quartic centrifugal distortion constants, and nuclear quadrupole coupling constants for gold and chlorine have been determined. The use of the nuclear spin-nuclear spin interaction terms Daa, Dbb, and Dcc for H2 were required …

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