Results for "W. -H. Fan"

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Short-living supermassive magnetar model for the early X-ray flares following short GRBsDec 30 2005Sep 14 2006We suggest a short-living supermassive magnetar model to account for the X-ray flares following short $\gamma-$ray bursts. In this model, the central engine of the short $\gamma-$ray bursts is a supermassive millisecond magnetar. The X-ray flares are ... More
$^1S_0$ pairing in neutron matterJul 23 2017We report calculations of the superfluid pairing gap in neutron matter for the $^1S_0$ components of the Reid soft-core $V_6$ and the Argonne $V_{4}'$ two-nucleon interactions. Ground-state calculations have been carried out using the central part of ... More
Finite difference schemes for the tempered fractional LaplacianNov 14 2017The second and all higher order moments of the $\beta$-stable L\'{e}vy process diverge, the feature of which is sometimes referred to as shortcoming of the model when applied to physical processes. So, a parameter $\lambda$ is introduced to exponentially ... More
The electron-phonon theory of superconductors: Tc map and vertex correctionFeb 04 2010Mar 30 2010The strong coupling Eliashberg theory plus vertex correction is used to calculate maps of transition temperature (Tc) in parameter-space characterizing superconductivity. Based on these Tc maps, crossover behaviors are found when electron-phonon interaction ... More
A STM model for Kondo Resonance on surface based on Schwinger-Keldysh ContourJul 29 2004Sep 22 2004The paper had been withdrawn due to some technical problems. New version will be uploaded near future.
Anomalous isotope effects of fulleride superconductorsNov 24 2008The numerical calculations of the standard Eliashberg-Nambu strong coupling theory and a formula of isotope effect derived in this paper provide direct evidences that an-harmonic vibrations of lattice enhance isotope effect with anomalous coefficient ... More
The Three-dimensional Evolution of Rising, Twisted Magnetic Flux Tubes in a Gravitationally Stratified Model Convection ZoneApr 04 2000We present three-dimensional numerical simulations of the rise and fragmentation of twisted, initially horizontal magnetic flux tubes which evolve into emerging Omega-loops. The flux tubes rise buoyantly through an adiabatically stratified plasma that ... More
The Effects of Rotation on the Evolution of Rising Omega-loops in a Stratified Model Convection ZoneAug 30 2000We present three-dimensional MHD simulations of buoyant magnetic flux tubes that rise through a stratified model convection zone in the presence of solar rotation. The equations of MHD are solved in the anelastic approximation, and the results are used ... More
Electronic bandstructure and optical gain of lattice matched III-V dilute nitride bismide quantum wells for 1.55 $μ$m optical communication systemsJun 21 2017Dilute nitride bismide GaNBiAs is a potential semiconductor alloy for near- and mid-infrared applications, particularly in 1.55 $\mu$m optical communication systems. Incorporating dilute amounts of Bismuth (Bi) into GaAs reduces the effective bandgap ... More
Testing quantum entanglement with local measurementOct 14 2011Apr 17 2012We propose to detect quantum entanglement by a condition of local measurments. We find that this condition can detect efficiently the pure entangled states for both discrete and continuous variable systems. It does not depend on interference of decoherence ... More
Quark models of dibaryon resonances in nucleon-nucleon scatteringJun 03 2008Jan 30 2009We look for $\Delta\Delta$ and $N\Delta$ resonances by calculating $NN$ scattering phase shifts of two interacting baryon clusters of quarks with explicit coupling to these dibaryon channels. Two phenomenological nonrelativistic chiral quark models giving ... More
Long-term Variability Properties and Periodicity Analysis for BlazarsJan 04 2000In this paper, the compiled long-term optical and infrared measurements of some blazars are used to analyze the variation properties and the optical data are used to search for periodicity evidence in the lightcurve by means of the Jurkevich technique ... More
Relation between $γ$-rays and emission lines for the $γ$-ray loud blazarsJul 21 2000The relation between the $\gamma$-ray and the emission line luminosities for a sample of 36 $\gamma$-ray loud blazars is investigated; an apparent correlation between them, $L_{\gamma} \propto L_{Line}^{0.69\pm0.11}$, with a correlation coefficient $r=0.741$ ... More
Measuring the Deviation from the Linear and Deterministic Bias through Cosmic Gravitational Lensing EffectsAug 19 2003Since gravitational lensing effects directly probe inhomogeneities of dark matter, lensing-galaxy cross-correlations can provide us important information on the relation between dark matter and galaxy distributions, i.e., the bias. In this paper, we propose ... More
The basic parameters of gamma-ray-loud blazarsMar 31 2005We determined the basic parameters, such as the central black hole mass ($M$), the boosting factor (or Doppler factor) ($\delta$), the propagation angle ($\Phi$) and the distance along the axis to the site of $\gamma$-ray production ($d$) for 23 $\gamma$-ray-loud ... More
Long-term infrared variation of 3C 279 and 4C 29.45Aug 07 1999In this paper, the historical infrared (JHK) data compiled from 22 publications are presented for 3C279 and 4C29.45. Relation between color index and magnitude and between color-color indices are discussed. (J-K) is found closely correlated with (J-H) ... More
BL Lac Objects and Relativistic Beaming ModelSep 02 1998In this paper: 1. The assumption of the dependence of Doppler factor on the emission frequency (Fan et al. 1993) is used to explain the observational differences between the radio-selected BL Lac objects(RBLs) and the X-Ray-Selected BL Lac objects (XBLs): ... More
Intrinsic alignments of galaxies and their effects on weak lensing detections of mass concentrationsJun 27 2007In this paper we investigate the influence of the intrinsic alignment of background galaxies on weak lensing detections of mass concentrations. Specifically, we analyze the number counts of false peaks resulting from intrinsic ellipticities in lensing ... More
Unbounded quantum Fisher information in two-path interferometry with finite photon numberMay 16 2011Jan 16 2013The minimum error of unbiased parameter estimation is quantified by the quantum Fisher information in accordance to the Cram\'{e}r-Rao bound. We indicate that only superposed NOON states by simultaneous measurements can achieve the maximum quantum Fisher ... More
Implementation of many-qubit Grover search by cavity QEDAug 21 2008Oct 07 2008We study the possibility of an implementation of N-qubit (N>3) Grover search in cavity QED, based on a fast operation of N-qubit controlled phase-flip with atoms in resonance with the cavity mode. We demonstrate both analytically and numerically that, ... More
Chandra and MMT observations of low-mass black hole active galactic nuclei accreting at low rates in dwarf galaxiesJan 21 2014We report on Chandra X-ray observations of four candidate low-mass black hole (<10^6Msun) active galactic nuclei (AGNs) that have the estimated Eddington ratios among the lowest (~10^(-2)) found for this class. The aims are to validate the nature of their ... More
Infrared Variation of BlazarsOct 14 1999In this paper, the historical infrared (JHK) data compiled from the published literature are presented here for 30 blazars. Maximum near-IR variations are found and compared with the optical ones. For the color-magnitude relation, some objects show that ... More
The two-qubit controlled-phase gate based on cross-phase modulation in GaAs/AlGaAs semiconductor quantum wellsJan 17 2012Jan 18 2012We present a realization of two-qubit controlled-phase gate, based on the linear and nonlinear properties of the probe and signal optical pulses in an asymmetric GaAs/AlGaAs double quantum wells. It is shown that, in the presence of cross-phase modulation, ... More
A simple way to detect the state transition caused by the nondiagonal abelian Berry phaseDec 12 2001May 02 2002In a nondegenerate syste, the abelian Berry's phase will never cause transitions among the Hamiltonian's eigenstate. However, in a degenerate syatem, it is well known that the state transition can be caused by the non-abelian Berry phase. Actually, in ... More
Magnetism of 3d transition metal atom on Au(110)-(1x2) and Au(111) surfacesJul 29 2004Jun 07 2007We calculate the magnetism of 3d transition metals on Au(110)-(1$\times$2) surface and Au(111) surface based on the Density Functional Theory. Our results show that the spin moments of the two-side elements of the 3d group such as Ti, V, Co and Ni decrease ... More
Three-dimensional interstellar dust reddening maps of the Galactic planeJul 06 2018Dec 05 2018We present new three-dimensional (3D) interstellar dust reddening maps of the Galactic plane in three colours, E(G-Ks), E(Bp-Rp) and E(H-Ks). The maps have a spatial angular resolution of 6 arcmin and covers over 7000 deg$^2$ of the Galactic plane for ... More
Monte Carlo Simulation of Surface De-alloying of Au/Ni(110)Mar 10 2004Jul 25 2004Based on BFS model and using Monte Carlo simulation we confirms the de-alloying in immiscible Au/Ni(110) system, and the critical Au coverage when de-alloying happens is also consistent with experiments. At the same time our simulation show that the structural ... More
Performance Bounds on a Wiretap Network with Arbitrary Wiretap SetsDec 01 2012Oct 12 2014Consider a communication network represented by a directed graph $\mathcal{G}=(\mathcal{V},\mathcal{E})$, where $\mathcal{V}$ is the set of nodes and $\mathcal{E}$ is the set of point-to-point channels in the network. On the network a secure message $M$ ... More
Magnetism of One-Dimensional Ni monoatomic chain on Au(110)-(1x2) surfaceJul 29 2004Jun 07 2007Based on Density Functional Theory with no-collinear-magnetism formulations, we have calculated magnetic anisotropy of supported Ni chains. Our results indicate that the magnetic anisotropy is closely related to orbital quenching. The easiest magnetized ... More
Spin orbit coupling controlled spin pumping effectAug 03 2015Sep 18 2015Effective spin mixing conductance (ESMC) across the nonmagnetic metal (NM)/ferromagnet interface, spin Hall conductivity (SHC) and spin diffusion length (SDL) in the NM layer govern the functionality and performance of pure spin current devices with spin ... More
Distinguishing Spontaneous Quantum Hall States in Graphene BilayersJul 24 2011Chirally stacked N-layer graphene with N>=2 is susceptible to a variety of distinct broken symmetry states in which each spin-valley flavor spontaneously transfers charge between layers. In mean-field theory the neutral bilayer ground state is a layer ... More
Whittaker models for depth zero representations of covering groupsMay 22 2017We study the dimension of the space of Whittaker functionals for depth zero representations of covering groups. In particular, we determine such dimensions for arbitrary Brylinski-Deligne coverings of the general linear group. The results in the paper ... More
Charged Black Holes in Colored Lifshitz SpacetimesJan 08 2015Jan 16 2015We consider Einstein gravities coupled to a cosmological constant and $SU(2)$ Yang-Mills fields in four and five dimensions. We find that the theories admit colored Lifshitz solutions with dynamic exponents $z>1$. We study the wave equations of the $SU(2)$ ... More
Electrically-Charged Lifshitz Spacetimes, and Hyperscaling ViolationsJan 21 2015Electrically-charged Lifshitz spacetimes are hard to come by. In this paper, we construct a class of such solutions in five dimensional Einstein gravity coupled to Maxwell and $SU(2)$ Yang-Mills fields. The solutions are electrically-charged under the ... More
SU(2)-Colored (A)dS Black Holes in Conformal GravityNov 19 2014Jan 12 2015We consider four-dimensional conformal gravity coupled to the U(1) Maxwell and SU(2) Yang-Mills fields. We study the structure of general black hole solutions carrying five independent parameters: the mass, the electric U(1) and magnetic SU(2) charges, ... More
Spectral Energy Distributions for TeV BlazarsMay 09 2018In this work, we collected a sample of 69 TeV blazars from TeVCat, obtained their multi-wavelength observations, and fitted their spectral energy distributions by using the second degree polynomial function. The structure parameters of the synchrotron ... More
Static and Dynamic Hairy Planar Black HolesMay 13 2015We consider Einstein gravity in general dimensions, coupled to a scalar field either minimally or non-minimally, together with a generic scalar potential. By making appropriate choices of the scalar potential, we obtain large classes of new scalar hairy ... More
Thermodynamical First Laws of Black Holes in Quadratically-Extended GravitiesDec 30 2014Feb 13 2015Einstein gravities in general dimensions coupled to a cosmological constant and extended with quadratic curvature invariants admit a variety of black holes that may asymptote to Minkowski, anti-de Sitter or Lifshitz spacetimes. We adopt the Wald formalism ... More
Comparison between TeV and non-TeV BL Lac ObjectsApr 21 2016Jun 15 2016BL Lacertae objects (BL Lacs) is the dominant population of TeV emitting blazars. In this work, we investigate whether there is any special observational properties for TeV sources. To do so, we will compare the observational properties of TeV detected ... More
Parity breaking and scaling behavior in light-matter interactionNov 18 2012Mar 13 2013The light-matter interaction described by Rabi model and Jaynes-Cummings (JC) model is investigated by parity breaking as well as the scaling behavior of ground-state population-inversion expectation. We show that the parity breaking leads to different ... More
Charged Black Holes with Scalar HairJul 15 2015Sep 22 2015We consider a class of Einstein-Maxwell-Dilaton theories, in which the dilaton coupling to the Maxwell field is not the usual single exponential function, but one with a stationary point. The theories admit two charged black holes: one is the Reissner-Nordstr{\o}m ... More
Quantum discord: "discord" between the whole and its constituentDec 13 2011Mar 02 2013Quantum discord, a measure of quantum correlation beyond entanglement, is initially defined as the discord between two classically equivalent while quantum discordant definitions of mutual information. In this paper, we report some new interpretations ... More
Purification of Single Photons from Room-Temperature Quantum DotsOct 04 2017Single photon emitters are indispensable to photonic quantum technologies. Here we demonstrate waveform-controlled high-purity single photons from room-temperature colloidal quantum dots. The purity of the single photons does not vary with the excitation ... More
Raman spectroscopy of epitaxial graphene on a SiC substrateMar 13 2008The fabrication of epitaxial graphene (EG) on SiC substrate by annealing has attracted a lot of interest as it may speed up the application of graphene for future electronic devices. The interaction of EG and the SiC substrate is critical to its electronic ... More
Passivation-sensitive exciton finestructure produces excess Stokes shifts in colloidal quantum dotsAug 17 2016The excitonic finestructure of colloidal quantum dots (CQDs) is comprised of a manifold of transitions, of which only the lowest are populated and contribute to photoluminescence. This leads to a Stokes shift in emission relative to absorption. Here we ... More
Anomalous Raman Spectra and Thickness Dependent Electronic properties of WSe2Mar 23 2013Apr 09 2013Typical Raman spectra of transition metal dichalcogenides (TMDs) display two prominent peaks, E2g and A1g, that are well separated from each other. We find that these modes are degenerate in bulk WSe2 yielding one single Raman peak. As the dimensionality ... More
Sorption of Eu(III) on Attapulgite Studied by Batch, XPS and EXAFS TechniquesDec 04 2009The effects of pH, ionic strength and temperature on sorption of Eu(III) on attapulgite were investigated in the presence and absence of fulvic acid (FA) and humic acid (HA). The results indicated that the sorption of Eu(III) on attapulgite was strongly ... More
A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulatorOct 10 2014Nov 25 2014We demonstrate an optical frequency comb based on an erbium-doped-fiber femtosecond laser with the nonlinear polarization evolution scheme. The repetition rate of the laser is about 209 MHz. By controlling an intra-cavity electro-optic modulator and a ... More
Galvanomagnetic effects and manipulation of antiferromagnetic interfacial uncompensated magnetic moment in exchange-biased bilayersMar 02 2014Oct 08 2014In this work, IrMn$_{3}$/insulating-Y$_{3}$Fe$_{5}$O$_{12}$ exchange-biased bilayers are studied. The behavior of the net magnetic moment $\Delta m_{AFM}$ in the antiferromagnet is directly probed by anomalous and planar Hall effects, and anisotropic ... More
Terahertz metamaterials on free-standing highly-flexible polyimide substratesAug 04 2008We have fabricated resonant terahertz metamaterials on free standing polyimide substrates. The low-loss polyimide substrates can be as thin as 5.5 micron yielding robust large-area metamaterials which are easily wrapped into cylinders with a radius of ... More
NIR spectroscopy of SDSS J0303-0019: a low luminosity, high Eddington ratio quasar at z~6Jul 02 2009We present sensitive near--infrared VLT ISAAC spectroscopic observations of the z=6.08 quasar SDSS J030331.40-001912.9. This QSO is more than a magnitude fainter than other QSOs at z~6 for which NIR spectroscopy has been obtained to date and is therefore ... More
Intrinsic Correlations for Flaring Blazars Detected by FermiFeb 19 2017Blazars are an extreme subclass of active galactic nuclei. Their rapid variability, luminous brightness, superluminal motion, and high and variable polarization are probably due to a beaming effect. However, this beaming factor (or Doppler factor) is ... More
Strain engineering and one-dimensional organization of metal-insulator domains in single-crystal VO2 beamsJul 27 2009Spatial phase inhomogeneity at the nano- to microscale is widely observed in strongly-correlated electron materials. The underlying mechanism and possibility of artificially controlling the phase inhomogeneity are still open questions of critical importance ... More
Indirect-direct hybrid-drive work-dominated hotspot ignition for inertial confinement fusionMar 31 2015An indirect-direct hybrid-drive work-dominated hotspot ignition scheme for inertial confinement fusion is proposed: a layered fuel capsule inside a spherical hohlraum with an octahedral symmetry is compressed first by indirect-drive soft-x rays (radiation) ... More
Spectral Energy Distributions of QSOs at z>5: common AGN-heated dust and occasionally strong star-formationFeb 24 2014We present spectral energy distributions (SEDs) of 69 QSOs at z>5, covering a rest frame wavelength range of 0.1mu to ~80mu, and centered on new Spitzer and Herschel observations. The detection rate of the QSOs with Spitzer is very high (97% at lambda_rest ... More
Thermopower and thermal conductivity of superconducting perovskite $MgCNi_3$Jul 17 2001Dec 01 2001The thermopower and thermal conductivity of superconducting perovskite $MgCNi_3$ ($T_c \approx$ 8 K) have been studied. The thermopower is negative from room temperature to 10 K. Combining with the negative Hall coefficient reported previously, the negative ... More
Complete infrared spectral energy distributions of mm detected quasars at z>5May 17 2013We present Herschel far-infrared (FIR) photometry of eleven quasars at redshift z>5 that have previously been detected at 1.2mm. We perform full spectral energy distribution (SED) fits over the wavelength range lambda_rest ~0.1-400mu for those objects ... More
Change-Point Testing and Estimation for Risk Measures in Time SeriesSep 07 2018We investigate methods of change-point testing and confidence interval construction for nonparametric estimators of expected shortfall and related risk measures in weakly dependent time series. A key aspect of our work is the ability to detect general ... More
Atomistic simulation of sub-nanosecond non-equilibrium field cooling processes for magnetic data storage applicationsSep 25 2014Thermally assisted magnetic writing is an important technology utilizing temperature dependent magnetic properties to enable orientation of a magnetic data storage medium. Using an atomistic spin model we study non-equilibrium field cooled magnetization ... More
Rotating Solar Jets in Simulations of Flux Emergence with Thermal ConductionJun 09 2014We study the formation of coronal jets through numerical simulation of the emergence of a twisted magnetic flux rope into a pre-existing open magnetic field. Reconnection inside the emerging flux rope in addition to that between the emerging and pre-existing ... More
Differentiable Learning of Logical Rules for Knowledge Base ReasoningFeb 27 2017Nov 27 2017We study the problem of learning probabilistic first-order logical rules for knowledge base reasoning. This learning problem is difficult because it requires learning the parameters in a continuous space as well as the structure in a discrete space. We ... More
Modeling two-state cooperativity in protein foldingMar 19 2001A protein model with the pairwise interaction energies varying as local environment changes, i.e., including some kinds of collective effect between the contacts, is proposed. Lattice Monte Carlo simulations on the thermodynamical characteristics and ... More
Significant contribution of As 4p orbitals to the low-lying electronic structure of 112-type iron-based superconductor Ca0.9La0.1FeAs2Nov 20 2014We report a systematic polarization-dependent angle-resolved photoemission spectroscopy study of the three-dimensional electronic structure of the recently discovered 112-type iron-based superconductor Ca1-xLaxFeAs2 (x = 0.1). Besides the commonly reported ... More
Observation of topological transition in high-T$_{c}$ superconductor FeTe$_{1-x}$Se$_{x}$/SrTiO$_{3}$(001) monolayersMar 14 2019Superconductors with topological surface or edge states have been intensively explored for the prospect of realizing Majorana bound states, which obey non-Abelian statistics and are crucial for topological quantum computation. The traditional routes for ... More
Detection of Aneuploidy with Digital PCRMay 08 2007The widespread use of genetic testing in high risk pregnancies has created strong interest in rapid and accurate molecular diagnostics for common chromosomal aneuploidies. We show here that digital polymerase chain reaction (dPCR) can be used for accurate ... More
Systematic errors in the determination of Hubble constant due to the asphericity and non-isothermality of clusters of galaxiesFeb 06 2006Joint analyses on X-ray and Sunyaev-Zel'dovich (SZ) effect of a cluster of galaxies can give rise to an estimate on the angular diameter distance to the cluster. With the redshift information of the cluster, the Hubble constant $H_0$ can then be derived. ... More
Effects of the complex mass distribution of dark matter halos on weak lensing cluster surveysAug 24 2005Gravitational lensing effects arise from the light ray deflection by all of the mass distribution along the line of sight. It is then expected that weak lensing cluster surveys can provide us true mass-selected cluster samples. With numerical simulations, ... More
Competing Ordered States in Bilayer GrapheneMay 24 2012We use a perturbative renormalization group approach with short-range continuum model interactions to analyze the competition between isotropic gapped and anisotropic gapless ordered states in bilayer graphene, commenting specifically on the role of exchange ... More
Infrared Variation of Radio Selected BL Lacertae ObjectsAug 10 1999In this paper, the historical infrared (JHK) data compiled from the published literature are presented in electronic form for 40 radio selected BL Lacertae objects (RBLs) for the first time. Largest variations are found and compared with the largest optical ... More
Pseudospin Order in Monolayer, Bilayer, and Double-Layer GrapheneSep 01 2011Jan 18 2012Graphene is a gapless semiconductor in which conduction and valence band wavefunctions differ only in the phase difference between their projections onto the two sublattices of the material's two-dimensional honeycomb crystal structure. We explain why ... More
An adaptive Metropolis-Hastings scheme: sampling and optimizationApr 07 2005We propose an adaptive Metropolis-Hastings algorithm in which sampled data are used to update the proposal distribution. We use the samples found by the algorithm at a particular step to form the information-theoretically optimal mean-field approximation ... More
Random Beamforming in Millimeter-Wave NOMA NetworksJul 21 2016Mar 16 2017This paper investigates the coexistence between two key enabling technologies for the fifth generation (5G) mobile networks, non-orthogonal multiple access (NOMA) and millimeter-wave (mmWave) communications. Particularly, the application of random beamforming ... More
SU(3) Quantum Hall Ferromagnetism in SnTeJul 12 2015The (111) surface of SnTe hosts one isotropic $\bar{\Gamma}$-centered and three degenerate anisotropic $\bar{M}$- centered Dirac surface states. We predict that a nematic phase with spontaneously broken $C_3$ symmetry will occur in the presence of an ... More
The distribution of two-dimensional eccentricity of Sunyaev-Zeldovich Effect and X-ray surface brightness profilesSep 07 2004Sep 08 2004With the triaxial density profile of dark matter halos and the corresponding equilibrium gas distribution, we derive two-dimensional Sunyaev-Zeldovich (SZ) effect and X-ray surface brightness profiles for clusters of galaxies. It is found that the contour ... More
The Effects of Relativistic Corrections on Cosmological Parameter Estimations from SZE Cluster SurveysAug 18 2003Sunyaev-Zel'dovich Effect (SZE) cluster surveys are anticipated to yield tight constraints on cosmological parameters such as the equation of state of dark energy. In this paper, we study the impact of relativistic corrections of the thermal SZE on the ... More
Impact of User Pairing on 5G Non-Orthogonal Multiple AccessDec 08 2014Non-orthogonal multiple access (NOMA) represents a paradigm shift from conventional orthogonal multiple access (MA) concepts, and has been recognized as one of the key enabling technologies for 5G systems. In this paper, the impact of user pairing on ... More
Imperfect Secrecy in Wiretap Channel IIFeb 04 2012Oct 12 2014In a point-to-point communication system which consists of a sender, a receiver and a set of noiseless channels, the sender wishes to transmit a private message to the receiver through the channels which may be eavesdropped by a wiretapper. The set of ... More
The variability analysis of PKS 2155-304Jan 04 2000In this paper, the post-1977 photometric observations of PKS 2155-304 are compiled and used to discuss the variation periodicity. Largest amplitude variations ($\Delta U = 1^{m}.5$; $\Delta B = 1^{m}.65$; $\Delta V = 1^{m}.85 $; $\Delta R = 1^{m}.25$; ... More
Random Beamforming in Millimeter-Wave NOMA NetworksJul 21 2016This paper investigates the coexistence between two key enabling technologies for the fifth generation (5G) mobile networks, non-orthogonal multiple access (NOMA) and millimeter-wave (mmWave) communications. Particularly, the application of random beamforming ... More
Hund's Rules for the N=0 Landau Levels of Trilayer GrapheneJan 26 2012The N=0 Landau levels of ABC and ABA trilayer graphene both have approximate 12-fold degeneracies that are lifted by interactions to produce strong quantum Hall effects (QHE) at all integer filling factors between nu=-6 and nu=6. We discuss similarities ... More
Impact of Non-orthogonal Multiple Access on the Offloading of Mobile Edge ComputingApr 18 2018This paper considers the coexistence of two important communication techniques, non-orthogonal multiple access (NOMA) and mobile edge computing (MEC). Both NOMA uplink and downlink transmissions are applied to MEC, and analytical results are developed ... More
Lattice Theory of Pseudospin Ferromagnetism in Bilayer Graphene: Competing Orders and Interaction Induced Quantum Hall StatesOct 09 2010Nov 29 2010In mean-field-theory bilayer graphene's massive Dirac fermion model has a family of broken inversion symmetry ground states with charge gaps and flavor dependent spontaneous inter layer charge transfers. We use a lattice Hartree-Fock model to explore ... More
Hydrogen Diffusion and Stabilization in Single-crystal VO2 Micro/nanobeams by Direct Atomic HydrogenationSep 16 2014We report measurements of the diffusion of atomic hydrogen in single crystalline VO2 micro/nanobeams by direct exposure to atomic hydrogen, without catalyst. The atomic hydrogen is generated by a hot filament, and the doping process takes place at moderate ... More
Realization of the Axion Insulator State in Quantum Anomalous Hall Sandwich HeterostructuresOct 02 2017Jan 03 2018The 'magnetoelectric effect' arises from the coupling between magnetic and electric properties in materials. The Z2 invariant of topological insulators (TIs) leads to a quantized version of this phenomenon, known as the topological magnetoelectric (TME) ... More
Chromium-Induced Ferromagnetism with Perpendicular Anisotropy in Topological Crystalline Insulator SnTe (111) Thin FilmsFeb 27 2018Topological crystalline insulator (TCI) is a recently-discovered topological phase of matter. It possesses multiple Dirac surface states, which are protected by the crystal symmetry. This is in contrast to the time reversal symmetry that is operative ... More
Paramagnetic ground state with field-induced partial order in Nd_3Ga_5SiO_{14} probed by low-temperature heat transportMay 17 2012We study the low-temperature heat transport of Nd_3Ga_5SiO_{14}, which is a spin-liquid candidate, to probe the nature of ground state and the effect of magnetic field on the magnetic properties. The thermal conductivity (\kappa) shows a purely phononic ... More
Tuning the electronic structure of Sr2IrO4 thin films by bulk electronic doping using molecular beam epitaxyApr 24 2015By means of oxide molecular beam epitaxy with shutter-growth mode, we have fabricated a series of electron-doped (Sr1-xLax)2IrO4(001)(x = 0, 0.05, 0.1 and 0.15) single crystalline thin films and then investigated the doping dependence of electronic structure ... More
Graphene based widely-tunable and singly-polarized pulse generation with random fiber lasersDec 11 2015Dec 22 2015Pulse generation often requires a stabilized cavity and its corresponding mode structure for initial phase-locking. Contrastingly, modeless cavity-free random lasers provide new possibilities for high quantum efficiency lasing that could potentially be ... More
Observation of the anisotropic Dirac cone in the band dispersion of 112-structured iron-based superconductor Ca0.9La0.1FeAs2Jul 30 2016CaFeAs2 is a parent compound of recently discovered 112-type iron-based superconductors. It is predicted to be a staggered intercalation compound that naturally integrates both quantum spin Hall insulating and superconducting layers and an ideal system ... More
Normal state resistivity, upper critical field and Hall effect in superconducting perovskite $MgCNi_3$Apr 28 2001Jun 02 2001The normal state resistivtity, upper critical field $H_{c2}$ and Hall coefficient $R_H$ in superconducting perovskite $MgCNi_3$ ($T_c \approx 8 K$) have been studied. Above 70 K, $\rho(T)$ fits well curve predicted by Bloch-Gr\"{u}neisen theory consistently ... More
The stabilizer dimension of graph statesJan 11 2009The entanglement properties of a multiparty pure state are invariant under local unitary transformations. The stabilizer dimension of a multiparty pure state characterizes how many types of such local unitary transformations existing for the state. We ... More
Origin of the kink in the band dispersion of the ferromagnetic perovskite SrRuO3: Electron-phonon couplingMar 09 2016Perovskite SrRuO3, a prototypical conductive ferromagnetic oxide, exhibits a kink in its band dispersion signalling the unusual electron dynamics therein. However, the origin of this kink remains elusive. By taking advantage of the combo of reactive molecular ... More
Surface electronic structure and evidence of plain s-wave superconductivity in (Li0.8Fe0.2)OHFeSeJul 09 2015Oct 04 2016(Li0.8Fe0.2)OHFeSe is a newly-discovered intercalated iron-selenide superconductor with a Tc above 40 K, which is much higher than the Tc of bulk FeSe (8 K). Here we report a systematic study of (Li0.8Fe0.2)OHFeSe by low temperature scanning tunneling ... More
New classes of chiral topological nodes with non-contractible surface Fermi arcs in CoSiJan 10 2019In condensed matter systems, chiral topological nodes are robust band crossing points in momentum space that carry nonzero Chern numbers. The chirality is manifested by the presence of surface Fermi arcs connecting the projections of nodes with opposite ... More
The optical microvariability and spectral changes of the BL Lacertae object S5 0716+714Oct 29 2009We monitored the BL Lac object S5 0716+714 in the optical band during October 2008, December 2008 and February 2009 with a best temporal resolution of about 5 minutes in the BVRI bands. Four fast flares were observed with amplitudes ranging from 0.3 to ... More
The Intrinsic $γ$-ray Emissions of $Fermi$ BlazarsMar 20 2017Beaming effect is important for the observational properties of blazars. In this work, we collect 91 $Fermi$ blazars with available radio Doppler factors. $\gamma$-ray Doppler factors are estimated and compared with radio Doppler factors for some sources. ... More
Radio variability properties for radio sourcesJan 18 2007In this paper, we used the database of the university of Michigan Radio Astronomy Observatory (UMRAO) at three (4.8 GHz, 8.0 GHZ, and 14.5 GHz) radio frequency to analyze the radio light curves by the power spectral analysis method in search of possible ... More
Periodic wave solutions of nonlinear equations by Hirota's bilinear methodFeb 08 2006In this paper, we use Hirota's bilinear method to directly construct periodic wave solutions of nonlinear equations. The asymptotic property of periodic wave solutions are analyzed. It is shown that well-known soliton solutions can be reduced from the ... More
Time-resolved magnetophotoluminescence studies of magnetic polaron dynamics in type-II quantum dotsOct 15 2015We used continuous wave photoluminescence (cw-PL) and time resolved photoluminescence (TR-PL) spectroscopy to compare the properties of magnetic polarons (MP) in two related spatially indirect II-VI epitaxially grown quantum dot systems. In the ZnTe/(Zn,Mn)Se ... More
The silicon matrix for the prototype for the Dark Matter Particle ExplorerMar 07 2014May 19 2014A new generation detector for the high energy cosmic ray - the DAMPE(DArk Matter Particle Explorer) is a satellite based project. Its main object is the measurement of energy spectrum of cosmic ray nuclei from 100GeV to 100TeV, the high energy electrons ... More