Results for "D. Zhao"

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Density cusps: restrictions on non-axisymmetric modelsJun 17 1997Jul 05 1997Galactic nuclei are now generally thought to have density cusps in their centres, and the evidence is mounting that as a consequence they are unlikely to be triaxial. Self-consistent stellar dynamical models of non-axisymmetric cusps would be an interesting ... More
Detecting relic gravitational waves in the CMB: Optimal parameters and their constraintsFeb 11 2009Mar 27 2009The prospect of detecting relic gravitational waves (RGWs), through their imprint in the cosmic microwave background radiation, provides an excellent opportunity to study the very early Universe. In simplest viable theoretical models the RGW background ... More
Better Image Segmentation by Exploiting Dense Semantic PredictionsJun 05 2016It is well accepted that image segmentation can benefit from utilizing multilevel cues. The paper focuses on utilizing the FCNN-based dense semantic predictions in the bottom-up image segmentation, arguing to take semantic cues into account from the very ... More
An octonion algebra originating in combinatoricsFeb 14 2010Jun 16 2010C.H. Yang discovered a polynomial version of the classical Lagrange identity expressing the product of two sums of four squares as another sum of four squares. He used it to give short proofs of some important theorems on composition of delta-codes (now ... More
Soliton interaction in a fiber ring laserOct 30 2009We have experimentally investigated the soliton interaction in a passively mode-locked fiber ring laser and revealed the existence of three types of strong soliton interaction: a global type of soliton interaction caused by the existence of unstable CW ... More
Geometry, Kinematics and Heliospheric Impact of a Large CME-driven Shock in 2017 SeptemberNov 26 2018A powerful coronal mass ejection (CME) occurred on 2017 September 10 near the end of the declining phase of the historically weak solar cycle 24. We obtain new insights concerning the geometry and kinematics of CME-driven shocks in relation to their heliospheric ... More
Faster and More Robust Mesh-based Algorithms for Obstacle k-Nearest NeighbourAug 13 2018We are interested in the problem of finding $k$ nearest neighbours in the plane and in the presence of polygonal obstacles ($\textit{OkNN}$). Widely used algorithms for OkNN are based on incremental visibility graphs, which means they require costly and ... More
A Geometrical Explanation of Stein ShrinkageMar 21 2012Shrinkage estimation has become a basic tool in the analysis of high-dimensional data. Historically and conceptually a key development toward this was the discovery of the inadmissibility of the usual estimator of a multivariate normal mean. This article ... More
Maximum Flux Transition Paths of Conformational ChangeAug 03 2009Jan 01 2010Given two metastable states A and B of a biomolecular system, the problem is to calculate the likely paths of the transition from A to B. Such a calculation is more informative and more manageable if done for a reduced set of collective variables chosen ... More
Molecular water accumulation on silica measured by land-contrast interferometry with picometer height resolutionAug 04 2009We observed water film accumulation on silica surfaces in the air to 2 picometer resolution using optical land-contrast (LC) interferometry. The land-contrast approach is non-destructive and allows real-time measurement of thickness variation of small ... More
Relic gravitational waves in the light of 7-year Wilkinson Microwave Anisotropy Probe data and improved prospects for the Planck missionMay 25 2010Aug 12 2010The new release of data from Wilkinson Microwave Anisotropy Probe improves the observational status of relic gravitational waves. The 7-year results enhance the indications of relic gravitational waves in the existing data and change to the better the ... More
Primordial Gravitational Waves and Cosmic Microwave Background RadiationApr 06 2010This is a summary of presentations delivered at the OC1 parallel session "Primordial Gravitational Waves and the CMB" of the 12th Marcel Grossmann meeting in Paris, July 2009. The reports and discussions demonstrated significant progress that was achieved ... More
Topological Classification and Stability of Fermi SurfacesNov 30 2012Jun 26 2013In the framework of the Cartan classification of Hamiltonians, a kind of topological classification of Fermi surfaces is established in terms of topological charges. The topological charge of a Fermi surface depends on its codimension and the class to ... More
Exotic Topological Types of Majorana Zero-modes and Their Universal Quantum ManipulationMay 16 2013Jan 19 2014From our general index theorem that characterises faithfully the boundary-bulk correspondence of topological superconductors and insulators, we reveal rigorously that four topologically distinct types of Majorana zero-modes can emerge at the ends of superconducting ... More
Decision table for classifying point sources based on FIRST and 2MASS databasesAug 31 2007With the availability of multiwavelength, multiscale and multiepoch astronomical catalogues, the number of features to describe astronomical objects has increases. The better features we select to classify objects, the higher the classification accuracy ... More
On multiserver retrial queues: history, Okubo-type hypergeometric systems and matrix continued-fractionsMar 08 2014We study two families of QBD processes with linear rates: (A) the multiserver retrial queue and its easier relative; and (B) the multiserver M/M/infinity Markov modulated queue. The linear rates imply that the stationary probabilities satisfy a recurrence ... More
On the structural stability of planar quasihomogeneous polynomial vector fieldsOct 19 2011Denote by $H_{pqm}$ the space of all planar $(p,q)$-quasihomogeneous vector fields of degree $m$ endowed with the coefficient topology. In this paper we characterize the set $\Omega_{pqm}$ of the vector fields in $H_{pqm}$ that are structurally stable ... More
Propagation and Interaction Properties of Successive Coronal Mass Ejections in Relation to a Complex Type II Radio BurstSep 29 2017We examine the propagation and interaction properties of three successive coronal mass ejections (CMEs) from 2001 November 21-22, with a focus on their connection with the behaviors of the associated long-duration complex type II radio burst. In combination ... More
Stable indications of relic gravitational waves in Wilkinson Microwave Anisotropy Probe data and forecasts for the Planck missionJul 07 2009Oct 21 2009The relic gravitational waves (gw) are the cleanest probe of the violent times in the very early history of the Universe. They are expected to leave signatures in the observed cosmic microwave background anisotropies. We significantly improved our previous ... More
On the road to discovery of relic gravitational waves: The TE and BB Correlations in the cosmic microwave background radiationOct 06 2008Jan 27 2009The detection of primordial gravitational waves is one of the biggest challenges of the present time. The existing (Wilkinson Microwave Anisotropy Probe) observations are helpful on the road to this goal, and the forthcoming experiments (Planck) are likely ... More
Detecting relics of a thermal gravitational wave background in the early UniverseJul 24 2009Sep 30 2009A thermal gravitational wave background can be produced in the early Universe if a radiation dominated epoch precedes the usual inflationary stage. This background provides a unique way to study the initial state of the Universe. We discuss the imprint ... More
Trapping radioactive ^{82}Rb in an optical dipole trap and evidence of spontaneous spin polarizationAug 28 2007Aug 28 2007Optical trapping of selected species of radioactive atoms has great potential in precision measurements for testing fundamental physics such as EDM, PNC and parity violating beta-decay asymmetry correlation coefficients. We report trapping of 10^4 radioactive ... More
Bound soliton fiber laserOct 30 2009Experimental study on the soliton dynamics of a passively mode locked fiber ring laser firstly revealed a state of bound soliton operation in the laser, where two solitons bind together tightly with fixed pulse separation. We further report on the properties ... More
Fractional Quantum Hall States at 1/3 and 5/2 Filling: the Density-Matrix Renormalization Group CalculationsMar 03 2011Apr 25 2011In this paper, the density-matrix renormalization group method is employed to investigate the fractional quantum Hall effect at filling fractions $\nu=1/3$ and 5/2. We first present benchmark results at both filling fractions for large system sizes to ... More
The Chromospheric Activity, Age, Metallicty and Space Motions of 36 Wide BinariesJan 17 2011We present the chromospheric activity (CA) levels, metallicities and full space motions for 41 F, G, K and M dwarf stars in 36 wide binary systems. Thirty-one of the binaries, contain a white dwarf component. In such binaries the total age can be estimated ... More
The Initial-Final Mass Relation among White Dwarfs in Wide BinariesDec 01 2011We present the initial-final mass relation derived from 10 white dwarfs in wide binaries that consist of a main sequence star and a white dwarf. The temperature and gravity of each white dwarf was measured by fitting theoretical model atmospheres to the ... More
Stellar Stream Candidates in the Solar Neighborhood Found in the LAMOST DR3 and TGASAug 05 2017We have cross-matched the LAMOST DR3 with the Gaia DR1 TGAS catalogs and obtained a sample of 166,827 stars with reliable kinematics. A technique based on the wavelet transform was applied to detect significant overdensities in velocity space among five ... More
Mechanism of multisoliton formation and soliton energy quantization in passively mode-locked fiber lasersOct 30 2009We report results of numerical simulations on the multiple soliton generation and soliton energy quantization in a soliton fiber ring laser passively mode-locked by using the nonlinear polarization rotation technique. We found numerically that the formation ... More
72 DA White Dwarfs Identified in LAMOST Pilot SurveyApr 12 2013We present a spectroscopically identified catalogue of 72 DA white dwarfs from the LAMOST pilot survey. 35 are found to be new identifications after cross-correlation with the Eisenstein et al. and Villanova catalogues. The effective temperature and gravity ... More
Three Moving Groups Detected in the LAMOST DR1 ArchiveMay 04 2014We analyze the kinematics of thick disk and halo stars observed by the Large sky Area Multi-Object Fiber Spectroscopic Telescope. We have constructed a sample of 7,993 F, G and K nearby main-sequence stars (\textit{d} $<$ 2 kpc) with estimates of position ... More
Penetration depth reduction with plasmonic metafilmsApr 16 2019In many optical systems, including metal films, dielectric reflectors, and photonic crystals, electromagnetic waves can experience evanescent decay. The spatial length scale of such decay defines the penetration depth. The ability to reduce the penetration ... More
Laser-assisted-autoionization dynamics of helium resonances with single attosecond pulsesMay 22 2012The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the 2s2p(1P) resonance state in the presence of an intense infrared (IR) laser. ... More
Self-started unidirectional operation of a fiber ring soliton laser without an isolatorOct 30 2009We demonstrate self-started mode-locking in an Erbium-doped fiber ring laser by using the nonlinear polarization rotation mode-locking technique but without an isolator in cavity. We show that due to the intrinsic effective nonlinearity discrimination ... More
A Convergent Iterative Solution of the Quantum Double-well PotentialMay 29 2001We present a new convergent iterative solution for the two lowest quantum wave functions $\psi_{ev}$ and $\psi_{od}$ of the Hamiltonian with a quartic double well potential $V$ in one dimension. By starting from a trial function, which is by itself the ... More
Convergent Iterative Solutions of Schroedinger Equation for a Generalized Double Well PotentialSep 13 2007We present an explicit convergent iterative solution for the lowest energy state of the Schroedinger equation with a generalized double well potential $V=\frac{g^2}{2}(x^2-1)^2(x^2+a)$. The condition for the convergence of the iteration procedure and ... More
Observation of polarization domain wall solitons in weakly birefringent cavity fiber lasersJul 31 2009We report on the experimental observation of two types of phase-locked vector soliton in weakly birefringent cavity erbium-doped fiber lasers. While a phase-locked dark-dark vector soliton was only observed in fiber lasers of positive dispersion, a phase-locked ... More
A Solar Eruption with Relatively Strong Geo-effectiveness Originating from Active Region Peripheral Diffusive PolaritiesJul 09 2018Jul 10 2018We report the observations of a moderate but relatively intense geo-effective solar eruption on 2015 November 4 from the peripheral diffusive polarities of active region 12443. We use space-borne Solar Dynamics Observatory and ACE observations. EUV images ... More
Iterative Solutions for Low Lying Excited States of a Class of Schroedinger EquationJul 12 2006The convergent iterative procedure for solving the groundstate Schroedinger equation is extended to derive the excitation energy and the wave function of the low-lying excited states. The method is applied to the one-dimensional quartic potential problem. ... More
Magnon squeezing in an antiferromagnet: reducing the spin noise below the standard quantum limitNov 13 2003At absolute zero temperature, thermal noise vanishes when a physical system is in its ground state, but quantum noise remains as a fundamental limit to the accuracy of experimental measurements. Such a limitation, however, can be mitigated by the formation ... More
Probing Molecular Dynamics at Attosecond Resolution with Femtosecond Laser PulsesJul 17 2003The kinetic energy distribution of D$^+$ ions resulting from the interaction of a femtosecond laser pulse with D$_2$ molecules is calculated based on the rescattering model. From analyzing the molecular dynamics, it is shown that the recollision time ... More
Two-color modulation transfer spectroscopyDec 07 2008We present two-color modulation transfer spectroscopy as a tool for precision studies of atomic properties of excited states. The bi-colored technique addresses a narrow set of velocity groups of a thermal atomic vapour using a two-step transition to ... More
Bound states of gain-guided solitons in a passively mode-locked fiber laserOct 30 2009We report on the observation of bound states of gain-guided solitons (GGSs) in a dispersion-managed erbium-doped fiber laser operating in the normal net cavity dispersion regime. Despite of the fact that the GGS is a chirped soliton and there is strong ... More
Multiwavelength Passively Mode Locked Fiber Laser: all normal dispersionApr 14 2009May 04 2009We report on the generation of multiwavelength gain-guided soliton (GGS) in an all normal dispersion birefringent fiber laser passively mode-locked with a semiconductor saturable absorber mirror (SESAM). Determined by the cavity birefringence, we observe ... More
Observation of high-order polarization-locked vector solitons in a fiber laserMar 13 2009We report on the experimental observation of a novel type of polarization locked vector soliton in a passively mode-locked fiber laser. The vector soliton is characterized by that not only the two orthogonally polarized soliton components are phase locked, ... More
Quantizing the Palatini action using a transverse traceless propagatorMay 20 2017Nov 30 2017We consider the first order form of the Einstein-Hilbert action and quantize it using the path integral. Two gauge fixing conditions are imposed so that the graviton propagator is both traceless and transverse. It is shown that these two gauge conditions ... More
Huygens-Fresnel wavefront tracing in non-uniform mediaSep 09 2015Jun 12 2016We present preliminary results on a novel numerical method describing wave propagation in non-uniform media. Following Huygens-Fresnel' principle, we model the wavefront as an array of point sources that emit wavelets, which interfere. We then identify ... More
Uniform Correlation Mixture of Bivariate Normal Distributions and Hypercubically-contoured Densities That Are Marginally NormalNov 19 2015The bivariate normal density with unit variance and correlation $\rho$ is well-known. We show that by integrating out $\rho$, the result is a function of the maximum norm. The Bayesian interpretation of this result is that if we put a uniform prior over ... More
Direct ultrashort pulse generation by intracavity nonlinear compressionOct 30 2009Direct generation of ultrashort, transform-limited pulses in a laser resonator is observed theoretically and experimentally. This constitutes a new type of ultrashort pulse generation in mode-locked lasers: in contrast to the well-known solitons (hyperbolic ... More
SlowFuzz: Automated Domain-Independent Detection of Algorithmic Complexity VulnerabilitiesAug 28 2017Algorithmic complexity vulnerabilities occur when the worst-case time/space complexity of an application is significantly higher than the respective average case for particular user-controlled inputs. When such conditions are met, an attacker can launch ... More
Feature functional theory - binding predictor (FFT-BP) for the blind prediction of binding free energiesMar 31 2017We present a feature functional theory - binding predictor (FFT-BP) for the protein-ligand binding affinity prediction. The underpinning assumptions of FFT-BP are as follows: i) representability: there exists a microscopic feature vector that can uniquely ... More
Averages of shifted convolutions of $d_3(n)$Jan 28 2011Feb 14 2011We investigate the first and second moments of shifted convolutions of the generalised divisor function $d_3(n)$.
Proof of a conjecture of Morales-Pak-Panova on reverse plane partitionsNov 08 2017Using equivariant cohomology theory, Naruse obtained a hook length formula for the number of standard Young tableaux of skew shape $\lambda/\mu$. Morales, Pak and Panova found two $q$-analogues of Naruse's formula respectively by counting semistandard ... More
Testing Alternative Theories of Dark Matter with the CMBMay 28 2008We propose a method to study and constrain modified gravity theories for dark matter using CMB temperature anisotropies and polarization. We assume that the theories considered here have already passed the matter power-spectrum test of large-scale structure. ... More
A Consistent Microlensing Model for the Galactic BarDec 11 1995We compute a microlensing map for the Galactic bar. The predicted event rate and event duration distribution are consistent with the $55$ events recently reported by the MACHO and OGLE collaborations. Most of the events are due to lensing by stars in ... More
Dark Pulse Emission of A Fiber LaserOct 30 2009We report on the dark pulse emission of an all-normal dispersion erbium-doped fiber laser with a polarizer in cavity. We found experimentally that apart from the bright pulse emission, under appropriate conditions the fiber laser could also emit single ... More
Coherent energy exchange between vector soliton components in fiber lasersMar 11 2009We report on the experimental evidence of four wave mixing (FWM) between the two polarization components of a vector soliton formed in a passively mode-locked fiber laser. Extra spectral sidebands with out-of-phase intensity variation between the polarization ... More
Nonadiabatic geometric quantum computation in decoherence-free subspaces based on unconventional geometric phasesDec 27 2016Nonadiabatic geometric quantum computation in decoherence-free subspaces has received increasing attention due to the merits of its high-speed implementation and robustness against both control errors and decoherence. However, all the previous schemes ... More
Propagation Characteristics of Two Coronal Mass Ejections From the Sun Far into Interplanetary SpaceFeb 14 2017Propagation of coronal mass ejections (CMEs) from the Sun far into interplanetary space is not well understood due to limited observations. In this study we examine the propagation characteristics of two geo-effective CMEs, which occurred on 2005 May ... More
Pairwise velocity dispersion of galaxies at high redshift: theoretical predictionsAug 23 2002We investigate the feasibility of determining the pairwise velocity dispersion (PVD) for Lyman Break Galaxies (LBGs), and of using this quantity as a discriminator among theoretical models. We find that when the Two Point Correlation Function over the ... More
Generalized Ito Formulae and Space-Time Lebesgue-Stieltjes Integrals of Local TimesMay 10 2005Aug 10 2015Generalised Ito formulae are proved for time dependent functions of continuous real valued semi-martingales. The conditions involve left space and time first derivatives, with the left space derivative required to have locally bounded 2-dimensional variation. ... More
Signatures of Bulge Triaxiality from Kinematics in Baade's Window/Sep 12 1994We study a sample of 62 Baade's Window (1,-4) K giants that have published proper motions, radial velocity and metallicity. We construct the velocity ellipsoids for the metal rich stars and metal poor stars. We find a vertex deviation characteristic of ... More
Anomalous Hall Effect in Chemically Disordered L10-Mn1.5GaDec 07 2013Jul 20 2016The anomalous Hall effect (AHE) in perpendicularly magnetized L10-Mn1.5Ga single-crystalline films is investigated as a function of degree of long-range chemical ordering and temperature. Our results provide firm evidence that phonons has negligibly smaller ... More
Multi-wavelength dissipative soliton operation of an erbium-doped fiber laserJul 10 2009We report on the generation of multi-wavelength dissipative soliton (DS) in an all normal dispersion fiber laser passively mode-locked with a semiconductor saturable absorber mirror (SESAM). We show that depending on the strength of the cavity birefringence, ... More
Efficient Task Collaboration with Execution UncertaintySep 17 2015We study a general task allocation problem, involving multiple agents that collaboratively accomplish tasks and where agents may fail to successfully complete the tasks assigned to them (known as execution uncertainty). The goal is to choose an allocation ... More
Incentive Design for Ridesharing with UncertaintyMay 07 2015We consider a ridesharing problem where there is uncertainty about the completion of trips from both drivers and riders. Specifically, we study ridesharing mechanisms that aim to incentivize commuters to reveal their valuation for trips and their probability ... More
An autoregressive approach to house price modelingApr 14 2011A statistical model for predicting individual house prices and constructing a house price index is proposed utilizing information regarding sale price, time of sale and location (ZIP code). This model is composed of a fixed time effect and a random ZIP ... More
Bound states of dispersion-managed solitons in a fiber laser at near zero dispersionOct 30 2009We report on the observation of various bound states of dispersion-managed (DM) solitons in a passively mode-locked Erbium-doped fiber ring laser at near zero net cavity group velocity dispersion (GVD). The generated DM solitons are characterized by their ... More
Convergent Iterative Solutions for a Sombrero-Shaped Potential in Any Space Dimension and Arbitrary Angular MomentumOct 25 2005We present an explicit convergent iterative solution for the lowest energy state of the Schroedinger equation with an $N$-dimensional radial potential $V=\frac{g^2}{2}(r^2-1)^2$ and an angular momentum $l$. For $g$ large, the rate of convergence is similar ... More
A New Method to Derive Low-Lying N-dimensional Quantum Wave Functions by Quadratures Along a Single TrajectoryMay 11 2000May 29 2000We present a new method to derive low-lying N-dimensional quantum wave functions by quadrature along a single trajectory. The N-dimensional Schroedinger equation is cast into a series of readily integrable first order ordinary differential equations. ... More
Relations Between Low-lying Quantum Wave Functions and Solutions of the Hamilton-Jacobi EquationOct 12 1999We discuss a new relation between the low lying Schroedinger wave function of a particle in a one-dimentional potential V and the solution of the corresponding Hamilton-Jacobi equation with -V as its potential. The function V is $\geq 0$, and can have ... More
Spiral Evolution in a Confined GeometryNov 21 2005Supported nanoscale lead crystallites with a step emerging from a non-centered screw dislocation on the circular top facet were prepared by rapid cooling from just above the melting temperature. STM observations of the top facet show a nonuniform rotation ... More
Magnetization, specific heat, and thermal conductivity of hexagonal ErMnO$_3$ single crystalsNov 09 2017We report a study of magnetism and magnetic transitions of hexagonal ErMnO$_3$ single crystals by magnetization, specific heat and heat transport measurements. Magnetization data show that the $c$-axis magnetic field induces three magnetic transitions ... More
Low-temperature heat transport of CuFe$_{1-x}$Ga$_x$O$_2$ ($x =$ 0--0.12) single crystalsMay 30 2017We report a study on the thermal conductivity of CuFe$_{1-x}$Ga$_x$O$_2$ ($x =$ 0--0.12) single crystals at temperatures down to 0.3 K and in magnetic fields up to 14 T. CuFeO$_2$ is a well-known geometrically frustrated triangular lattice antiferromagnet ... More
Heat switch effect in an antiferromagnetic insulator Co$_3$V$_2$O$_8$Jun 07 2016We report a heat switch effect in single crystals of an antiferromagnet Co$_3$V$_2$O$_8$, that is, the thermal conductivity ($\kappa$) can be changed with magnetic field in an extremely large scale. Due to successive magnetic phase transitions at 12--6 ... More
Thermal conductivity of the diamond-chain compound Cu_3(CO_3)_2(OH)_2Dec 17 2015Thermal conductivity (\kappa) of a distorted spin diamond-chain system, Cu_3(CO_3)_2(OH)_2, is studied at low temperatures down to 0.3 K and in magnetic fields up to 14 T. In zero field, the \kappa(T) curve with heat current along the chain direction ... More
A parity-breaking electronic nematic phase transition in the spin-orbit coupled metal Cd$_2$Re$_2$O$_7$Apr 24 2017Strong electron interactions can drive metallic systems toward a variety of well-known symmetry-broken phases, but the instabilities of correlated metals with strong spin-orbit coupling have only recently begun to be explored. We uncovered a multipolar ... More
Tracers of chromospheric structure. I. CaII H$\&$K emission distribution of 13000 F, G and K stars in SDSS DR7 spectroscopic sampleApr 12 2013We present chromospheric activity index $S\rm_{HK}$ measurements for over 13,000 F, G and K disk stars with high signal-to-noise ratio ($>$ 60) spectra in the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) spectroscopic sample. A parameter $\delta$S ... More
Magnetically originated phonon-glass-like behavior in Tb_2Ti_2O_7 single crystalMay 29 2013We report a study on the thermal conductivity (\kappa) of Tb_2Ti_2O_7 single crystals at low temperatures. It is found that in zero field this material has an extremely low phonon thermal conductivity in a broad temperature range. The mean free path of ... More
Radio structure of the blazar 1156+295 with sub-pc resolutionFeb 15 2011Apr 04 20111156+295 is a flat-spectrum quasar which is loud at radio and gamma-ray. Previous observations of the source revealed a radio morphology on pc to kpc scales consistent with a helical jet model. In our present research, this source was observed with the ... More
Three Mode Interactions as a Precision Monitoring Tool for Advanced Laser InterferometersFeb 20 2014Three-mode opto-acoustic interactions in advanced laser interferometer gravitational wave detectors have high sensitivity to thermally excited ultrasonic modes in their test masses. Three mode interaction signal gain can change by 100% for thermally induced ... More
Congruences for the Coefficients of the Powers of the Euler ProductFeb 05 2018Mar 13 2018Let $p_k(n)$ be given by the $k$-th power of the Euler Product $\prod _{n=1}^{\infty}(1-q^n)^k=\sum_{n=0}^{\infty}p_k(n)q^{n}$. By investigating the properties of the modular equations of the second and the third order under the Atkin $U$-operator, we ... More
Turbulence Model Development using CFD-Driven Machine LearningFeb 25 2019This paper presents a novel CFD-driven machine learning framework to develop Reynolds-averaged Navier-Stokes (RANS) models. For the CFD-driven training, the gene expression programming (GEP) method (Weatheritt & Sandberg, J. Comput. Phys., 325, 22-37 ... More
Fractional Quantum Hall Bilayers at Half-Filling: Tunneling-driven Non-Abelian PhaseAug 28 2016Multicomponent quantum Hall systems with internal degrees of freedom provide a fertile ground for the emergence of exotic quantum liquids. Here we investigate the possibility of non-Abelian topological order in the half-filled fractional quantum Hall ... More
A charge density wave-like instability in a doped spin-orbit-assisted weak Mott insulatorJan 18 2017Layered perovskite iridates realize a rare class of Mott insulators that are predicted to be strongly spin-orbit coupled analogues of the parent state of cuprate high-temperature superconductors. Recent discoveries of pseudogap, magnetic multipolar ordered ... More
Spectroscopic signature of the $\mathbf{k}$-dependent electron-phonon coupling in $2H$-TaS$_2$May 09 2018Our detailed Angle Resolved Photoemission Spectroscopy (ARPES) study of $2H$-TaS$_2$, a canonical incommensurate charge density wave (CDW) material, illustrates pronounced many-body renormalization in the system, which is manifested by the presence of ... More
LaPtSb: a half-Heusler compound with high thermoelectric performanceJan 28 2016Jun 07 2016The electronic and transport properties of the half-Heusler compound LaPtSb are investigated by performing first-principles calculations combined with semi-classical Boltzmann theory and deformation potential theory. Compared with many typical half-Heusler ... More
Neutron Scattering Measurements of Spatially Anisotropic Magnetic Exchange Interactions in Semiconducting K0.85Fe1.54Se2 (TN=280 K)May 19 2014We use neutron scattering to study the spin excitations associated with the stripe antiferromagnetic (AFM) order in semiconducting K$_{0.85}$Fe$_{1.54}$Se$_2$ ($T_N$=$280$ K). We show that the spin wave spectra can be accurately described by an effective ... More
Spectroscopic evidence for the convergence of lower and upper valence bands of PbQ (Q=Te, Se, S) with rising temperatureApr 07 2014Jul 03 2014We have conducted temperature dependent Angle Resolved Photoemission Spectroscopy (ARPES) study of the electronic structure of n-, p- type PbTe, PbSe and PbS, which are pre- mier thermoelectric materials. Our ARPES measurements on them provide direct ... More
Diffusion of particles in simple fluids: A joint theory of kinetics and hydrodynamicsJul 30 2016The particle diffusion in a fluid is a classical topic that dates back to more than one century ago. However, a full solution to this issue still lacks. In this work the velocity autocorrelation function and the diffusion constant are derived analytically, ... More
Description of Brownian motion including both kinetic and hydrodynamic effectsDec 02 2017Feb 12 2018It is known that a full description of Brownian motion in the entire course of time should incorporate both kinetic and hydrodynamic effects, but a formula accounts for both effects has been established only in three dimension and only for the limiting ... More
Tensor Networks for Dimensionality Reduction and Large-Scale Optimizations. Part 2 Applications and Future PerspectivesAug 30 2017Part 2 of this monograph builds on the introduction to tensor networks and their operations presented in Part 1. It focuses on tensor network models for super-compressed higher-order representation of data/parameters and related cost functions, while ... More
Lithium-ion battery thermal-electrochemical model-based state estimation using orthogonal collocation and a modified extended Kalman filterJun 29 2015This paper investigates the state estimation of a high-fidelity spatially resolved thermal- electrochemical lithium-ion battery model commonly referred to as the pseudo two-dimensional model. The partial-differential algebraic equations (PDAEs) constituting ... More
Properties of Short-wavelength Oblique Alfven and Slow WavesMay 04 2014Sep 13 2014Linear properties of kinetic Alfv\'{e}n waves (KAWs) and kinetic slow waves (KSWs) are studied in the framework of two-fluid magnetohydrodynamics. We obtain the wave dispersion relations that are valid in a wide range of the wave frequency $\omega $ and ... More
High-precision Distribution of Highly-stable Optical Pulse Trains with Sub-10-fs Timing JitterFeb 23 2014High-precision optical pulse trains distribution via fibre links has made huge impacts in many fields. In most published works, the accuracies are still fundamentally limited by some unavoidable noises, such as thermal and shot noise from conventional ... More
Trapping of dark vector solitons in a fiber laserApr 17 2009May 07 2009We report on the experimental observation of incoherently coupled dark vector soliton trapping in a fiber laser. Dark vector solitons along the two orthogonal polarization directions though with large difference in central frequency, energy and darkness ... More
An overview and perspective on social network monitoringMar 31 2016In this expository paper we give an overview of some statistical methods for the monitoring of social networks. We discuss the advantages and limitations of various methods as well as some relevant issues. One of our primary contributions is to give the ... More
Differential gene co-expression networks via Bayesian biclustering modelsNov 07 2014Identifying latent structure in large data matrices is essential for exploring biological processes. Here, we consider recovering gene co-expression networks from gene expression data, where each network encodes relationships between genes that are locally ... More
Valid Post-selection Inference in Assumption-lean Linear RegressionJun 11 2018Construction of valid statistical inference for estimators based on data-driven selection has received a lot of attention in the recent times. Berk et al. (2013) is possibly the first work to provide valid inference for Gaussian homoscedastic linear regression ... More
Spontaneous Decoherence of Coupled Harmonic Oscillators Confined in A RingSep 30 2016We study the spontaneous decoherence of the coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry breaking field or surrounding environment, ... More
GPU Based Parallel Ising Computing for Combinatorial Optimization Problems in VLSI Physical DesignJul 27 2018Mar 14 2019In VLSI physical design, many algorithms require the solution of difficult combinatorial optimization problems such as max/min-cut, max-flow problems etc. Due to the vast number of elements typically found in this problem domain, these problems are computationally ... More