Still searching Arxiv, refresh for possibly better results.

Results for "X. -X. Wu"

total 26850took 0.12s
Statistics of random lasing modes and amplified spontaneous emission spikes in weakly scattering systemsMar 28 2007We have measured the spectral correlations and intensity statistics of random lasing modes in weakly scattering systems, and compared them to those of the amplified spontaneous emission spikes. Their dramatic differences revealed the distinct physical ... More
Block model for the XY-type Landau-Ginzburg-Wilson Hamiltonian with an inhomogeneous temperatureJan 20 2012The phase fluctuation near the saddle point solution of the XY-type Landau-Ginzburg-Wilson Hamiltonian with random temperature is studied. For the modes with lowest eigenvalue, the systems is self-organized into blocks, which are coupled as a XY model ... More
Asymptotic Behavior of Error Exponents in the Wideband RegimeAug 31 2005In this paper, we complement Verd\'{u}'s work on spectral efficiency in the wideband regime by investigating the fundamental tradeoff between rate and bandwidth when a constraint is imposed on the error exponent. Specifically, we consider both AWGN and ... More
Predicting Unconventional High Temperature Superconductors in Trigonal Bipyramidal CoordinationsJun 12 2015Jun 19 2015Cuprates and iron-based superconductors are two classes of unconventional high Tc superconductors based on 3d transition elements. Recently, two principles, correspondence principle and magnetic selective pairing rule, have been emerged to unify their ... More
The fastest rotating pulsar: A strange star?Jan 01 2001Mar 28 2001According to the observational limits on the radius and mass, the fastest rotating pulsar (PSR 1937+21) is probably a strange star, or at least some neutron star equations of state should be ruled out, if we suggest that a dipole magnetic field is relevant ... More
Dissipation-based entanglement via quantum Zeno dynamics and Rydberg antiblockadeMay 10 2017A novel scheme is proposed for dissipative generation of maximally entanglement between two Rydberg atoms in the context of cavity QED. The spontaneous emission of atoms combined with quantum Zeno dynamics and Rydberg antiblockade guarantees a unique ... More
Dynamics of DistillabilityMay 30 2003The time evolution of a maximally entangled bipartite systems is presented in this paper. The distillability criterion is given in terms of Kraus operators. Using the criterion, we discuss the distillability of $2\times 2$ and $n\times n (n>2)$ systems ... More
The Dynamical Invariant of Open Quantum SystemOct 05 2015The dynamical invariant, whose expectation value is constant, is generalized to open quantum system. The evolution equation of dynamical invariant (the dynamical invariant condition) is presented for Markovian dynamics. Different with the dynamical invariant ... More
Dissipative stabilization of quantum-feedback-based multipartite entanglement with Rydberg atomsDec 31 2016A quantum-feedback-based scheme is proposed for generating multipartite entanglements of Rydberg atoms in a dissipative optical cavity. The Rydberg blockade mechanism efficiently prevents double excitations of the system, which is further exploited to ... More
Pion Form Factor in the $k_T$ Factorization FormalismApr 20 2004Jun 12 2004Based on the light-cone (LC) framework and the $k_T$ factorization formalism, the transverse momentum effects and the different helicity components' contributions to the pion form factor $F_{\pi}(Q^2)$ are recalculated. In particular, the contribution ... More
Tunneling of Micro-sized Droplets Through a Flowing Soap FilmAug 14 2017Aug 30 2018When a micron-sized water droplet impacts on a freely suspended soap film with speed $v_{i}$, there exists a critical impact velocity of penetration $v_{C}$. For the droplet with $v_{i}<v_{C}$, it flows with the soap film after the impact whereas with ... More
Quantum and Coulomb repulsion effects on the bubble structures in $^{204, 206}$HgSep 22 2018The decreasing proton and charge densities from around 5.0 fm towards the center of $^{204, 206}$Hg are investigated by a covariant density functional theory at the beyond mean-field level.The charge-density difference between $^{208}$Pb and $^{204}$Hg ... More
Influence of bulk inversion asymmetry on the magneto-optical spectrum of a HgTe topological insulatorSep 22 2013The influence of bulk inversion asymmetry in [001] and [013] grown HgTe quantum wells is investigated theoretically. The bulk inversion asymmetry leads to an anti-crossing gap between two zero-mode Landau levels in a HgTe topological insulator, i.e., ... More
Direct solutions for normal depths in curved irrigation canalsSep 02 2013The normal depth is an important hydraulic element for canal design, operation and management. Curved irrigation canals including parabola, U-shaped and catenary canals have excellent hydraulic performance and strong ability of anti-frost heave, while ... More
Exact wave functions for the edge state of a disk-shaped two dimensional topological insulatorSep 22 2013We report the exact wave functions for the eigen state of a disk-shaped two dimensional topological insulator. The property of the edge state whose energy lies inside the bulk gap is studied. It is found that the edge state energy is affected by the radius ... More
A Unified Strouhal-Reynolds Number Relationship for Laminar Vortex Streets Generated by Different Shaped ObstaclesAug 14 2017A new Strouhal-Reynolds number relationship, $St=1/(A+B/Re)$, has been recently proposed based on observations of laminar vortex shedding from circular cylinders in a flowing soap film. Since the new $St$-$Re$ relation was derived from a general physical ... More
Landau level transitions in InAs/AlSb/GaSb quantum wellsMar 12 2015The electronic structure of InAs/AlSb/GaSb quantum wells embedded in AlSb barriers and in the presence of a perpendicular magnetic field is studied theoretically within the $14$-band ${\bf k}\cdot{\bf p}$ approach without making the axial approximation. ... More
Efficiency of electrical manipulation on two-dimensional topological insulatorsSep 21 2013We investigate the efficiency of electrical manipulation on two-dimensional topological insulators by considering a lateral potential superlattice on the system. The electronic states under various conditions are examined carefully. It is found that the ... More
Nuclear symmetry energy and hadron-quark mixed phase in neutron starsNov 15 2018We study the hadron-quark mixed phase, which may occur in the interior of neutron stars. The relativistic mean-field model is employed to describe the hadronic phase, while the Nambu--Jona-Lasinio model is used for the quark phase. We examine the effects ... More
Ultra High Energy Cosmic Rays: Strangelets? -- Extra dimensions, TeV-scale black holes and strange matterDec 04 2002Mar 15 2003The conjecture that ultra high energy cosmic rays (UHECRs) are actually strangelets is discussed. Besides the reason that strangelets can do as cosmic rays beyond the GZK-cutoff, another argument to support the conjecture is addressed in this letter via ... More
Engineering steady-state entanglement via dissipation and quantum Zeno dynamics in optical cavityMay 18 2017Mar 06 2018A new mechanism is proposed for dissipatively preparing maximal Bell entangled state of two atoms in an optical cavity. This scheme integrates the spontaneous emission, the light shift of atoms in the presence of dispersive microwave field, and the quantum ... More
Ground-state blockade of Rydberg atoms and application in entanglement generationMay 08 2017Dec 06 2017We propose a mechanism of ground-state blockade between two $N$-type Rydberg atoms in virtue of Rydberg-antiblockade effect and Raman transition. Inspired by the quantum Zeno effect, the strong Rydberg antiblockade interaction plays a role in frequently ... More
Experimentally realizable control fields in quantum Lyapunov controlFeb 24 2011As a hybrid of techniques from open-loop and feedback control, Lyapunov control has the advantage that it is free from the measurement-induced decoherence but it includes the system's instantaneous message in the control loop. Often, the Lyapunov control ... More
Asteroseismology of the $δ$ Scuti star HD 50844Jun 30 2016Aims. We aim to probe the internal structure and investigate more detailed information of the $\delta$ Scuti star HD 50844 with asteroseismology. Methods. We analyse the observed frequencies of the $\delta$ Scuti star HD 50844 obtained by Balona (2014), ... More
Effective Hamiltonian Approach to Open Systems and Its ApplicationsOct 16 2008By using the effective Hamiltonian approach, we present a self-consistent framework for the analysis of geometric phases and dynamically stable decoherence-free subspaces in open systems. Comparisons to the earlier works are made. This effective Hamiltonian ... More
GRB 060206: hints of precession of the central engine?Aug 08 2008Aims. The high-redshift (z = 4:048) gamma-ray burst GRB 060206 showed unusual behavior, with a significant rebrightening by a factor of ~ 4 at about 3000 s after the burst. We argue that this rebrightening implies that the central engine became active ... More
Adsorption, Segregation and Magnetization of a Single Mn Adatom on the GaAs (110) SurfaceMar 21 2005Density functional calculations with a large unit cell have been conducted to investigate adsorption, segregation and magnetization of Mn monomer on GaAs(110). The Mn adatom is rather mobile along the trench on GaAs(110), with an energy barrier of 0.56 ... More
Effects of uncertainties and errors on Lyapunov controlOct 11 2010Lyapunov control (open-loop) is often confronted with uncertainties and errors in practical applications. In this paper, we analyze the robustness of Lyapunov control against the uncertainties and errors in quantum control systems. The analysis is carried ... More
Time-dependent Decoherence-Free SubspaceMay 07 2012Sep 20 2012With time-dependent Lindblad operators, an open system may have a time-dependent decoherence-free subspace (t-DFS). In this paper, we define the t-DFS and present a necessary and sufficient condition for the t-DFS. Two examples are presented to illustrate ... More
Berry Phase and Hannay's Angle in a Quantum-Classical Hybrid SystemMar 19 2011Berry phase, which had been discovered for more than two decades, provides us a very deep insight on the geometric structure of quantum mechanics. Its classical counterpart--Hannay's angle is defined if closed curves of action variables return to the ... More
Canonical Form and Separability of PPT States in 2x2x2xN Composite Quantum SystemsOct 23 2003We give a canonical form of PPT states in ${\cal C}^2 \otimes {\cal C}^2\otimes {\cal C}^2 \otimes {\cal C}^N$ with rank=$N$. From this canonical form a necessary separable condition for these states is presented.
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
Skyrmions in Higher Landau LevelsFeb 27 1995We calculate the energies of quasiparticles with large numbers of reversed spins (``skyrmions'') for odd integer filling factors 2k+1, k is greater than or equals 1. We find, in contrast with the known result for filling factor equals 1 (k = 0), that ... More
Multiscale simulation on shearing transitions of thin-film lubrication with multi-layer moleculesMay 29 2017Shearing transitions of multi-layer molecularly thin-film lubrication systems in variations of the film-substrate coupling strength and the load are studied by using a multiscale method. Three kinds of the interlayer slips found in decreasing the coupling ... More
Surface Junction in Bi$_2$Sr$_2$CaCu$_2$O$_{8+d}$ Single CrystalsMay 17 2003As nature junction geometry of the d-wave cuprate superconductor/insulator/the mixture of s-wave and d-wave cuprate superconductor, the upmost surface junction of intrinsic Josephson junction stack fabricated on Bi$_2$Sr$_2$CaCu$_2$O$_{8+d}$ single crystals ... More
Orientation of Galaxies in the Local Supercluster: A ReviewAug 31 2005The progress of the studies on the orientation of galaxies in the Local Supercluster (LSC) is reviewed and a summary of recent results is given. Following a brief introduction of the LSC, we describe the results of early studies based on two-dimensional ... More
Quakes in Solid Quark StarsApr 28 2004May 27 2004A starquake mechanism for pulsar glitches is developed in the solid quark star model. It is found that the general glitch natures (i.e., the glitch amplitudes and the time intervals) could be reproduced if solid quark matter, with high baryon density ... More
Born-Oppenheimer approximation for open quantum systems within the quantum trajectory approachMar 05 2010Apr 17 2010Based on the quantum trajectory approach, we extend the Born-Oppenheimer (BO) approximation from closed quantum system to open quantum system, where the open quantum system is described by a master equation in Lindblad form. The BO approximation is defined ... More
Half-metallicity in aluminum-doped zigzag silicene nanoribbonsAug 29 2014The spin-dependent electronic structures of aluminum-(Al) doped zigzag silicene nanoribbons (ZSiNRs) are investigated by first-principles calculations. When ZSiNRs are substitutionally doped by a single Al atom on different sites in every three primitive ... More
Dissipative preparation of steady Greenberger-Horne-Zeilinger states for Rydberg atoms with quantum Zeno dynamicsSep 25 2017Dec 06 2017Inspired by a recent work [Reiter, Reeb, and S{\o}rensen, Phys. Rev. Lett. {\bf117}, 040501 (2016)], we present a simplified proposal for dissipatively preparing a Greenberger-Horne-Zeilinger (GHZ) state of three Rydberg atoms in a cavity. The $Z$ pumping ... More
Fractional Quantum Hall States in Low-Zeeman-Energy LimitDec 22 1993We investigate the spectrum of interacting electrons at arbitrary filling factors in the limit of vanishing Zeeman splitting. The composite fermion theory successfully explains the low-energy spectrum {\em provided the composite fermions are treated as ... More
Anisotropy of Cosmic AccelerationMay 13 2013May 16 2013In this paper, we study the anisotropy of cosmic acceleration by dividing the Union2 Type Ia supernova dataset into 12 subsets according to their positions in Galactic coordinate system. In each region, we derive the deceleration parameter $q_0$ as the ... More
The Nature of the Diffuse Clumps and the X-ray Companion of Mrk 273May 17 1999We present an optical spectrum for Mrk 273x, the X-ray source 1.3' to the northeast of Mrk 273. The new spectrum indicates that the object is at a much higher redshift (0.458) than the value (0.0376) previously reported. All the detected emission lines ... More
Effect of iron-doping on spin-state transition and ferromagnetism in Pr$_{0.5}$Ca$_{0.5}$CoO$_{3-δ}$ cobalt oxidesSep 21 2005Resistivity and dc magnetization measurements were performed for the polycrystalline Pr$_{0.5}$Ca$_{0.5}$Co$_{1-x}$Fe$_{x}$O$_{3-\delta}$ ($x$ = 0, 0.05, 0.10 and 0.15) samples. The as-fabricated samples exhibit ferromagnetic (FM) transition and the transition ... More
Multilevel quantum Otto heat engines with identical particlesFeb 23 2018A quantum Otto heat engine is studied with multilevel identical particles trapped in one-dimensional box potential as working substance. The symmetrical wave function for Bosons and the anti-symmetrical wave function for Fermions are considered. In two-particle ... More
Excitation Spectrum of Composite FermionsMar 15 1994We show that the excitation spectrum of interacting electrons at filling factor $\nu=\nu^*/(2\nu^*+1)$ is well described in terms of non-interacting composite fermions at filling factor $\nu^*$, but does not have a one-to-one correspondence with the excitation ... More
Photonic band structure of ZnO photonic crystal slab laserMar 21 2005We recently reported on the first realization of ultraviolet photonic crystal laser based on zinc oxide [Appl. Phys. Lett. {\bf 85}, 3657 (2004)]. Here we present the details of structural design and its optimization. We develop a computational super-cell ... More
GRB 030226 in a Density-Jump MediumMay 22 2003We present an explanation for the unusual temporal feature of the GRB 030226 afterglow. The R-band afterglow of this burst faded as ~ t^{-1.2} in ~ 0.2 days after the burst, rebrightened during the period of ~ 0.2 - 0.5 days, and then declined with ~ ... More
The D0$-$D8 system revisitedSep 06 2009Oct 25 2009We address a few subtle issues regarding the interacting D0-D8 system. There are two existing interpretations for the counter-intuitive non-vanishing cylinder-diagram R-R potential. We improve them each by properly dealing with the divergence of potential ... More
The braking indices in pulsar emission modelsJul 20 2003Aug 23 2003Using the method proposed in a previous paper, we calculate pulsar braking indices in the models with torque contributions from both inner and outer accelerating regions, assuming that the interaction between them is negligible. We suggest that it is ... More
Quadrupole collectivity and shell closure in neutron-rich nuclei around $N=126$Feb 19 2019We present a comprehensive study on the low-lying states of neutron-rich Er, Yb, Hf, and W isotopes across the $N=126$ shell with a multi-reference covariant density functional theory. Beyond mean-field effects from shape mixing and symmetry restoration ... More
Exact results for polaron and molecule in one-dimensional spin-1/2 Fermi gasNov 03 2016Using exact Bethe ansatz (BA) solutions, we show that a spin-down fermion immersed into a fully polarized spin-up Fermi sea with a weak attraction is dressed by the surrounding spin-up fermions to form the one-dimensional analog of a polaron. As the attraction ... More
Information Flow, Non-Markovianity and Geometric PhasesNov 18 2010Geometric phases and information flows of a two-level system coupled to its environment are calculated and analyzed. The information flow is defined as a cumulant of changes in trace distance between two quantum states, which is similar to the measure ... More
Separability and entanglement in 2x3xN composite quantum systemsAug 28 2003The separability and entanglement of quantum mixed states in $\Cb^2 \otimes \Cb^3 \otimes \Cb^N$ composite quantum systems are investigated. It is shown that all quantum states $\rho$ with positive partial transposes and rank $r(\rho)\leq N$ are separable. ... More
Adiabatic Decoherence-Free Subspaces and its ShortcutsMay 04 2017Oct 24 2017The adiabatic theorem and "shortcuts to adiabaticity" for the adiabatic dynamics of time-dependent decoherence-free subspaces are explored in this paper. Starting from the definition of the dynamical stable decoherence-free subspaces, we show that, under ... More
Dynamics of quantum-classical hybrid system: effect of matter-wave pressureOct 21 2009Radiation pressure affects the kinetics of a system exposed to the radiation and it constitutes the basis of laser cooling. In this paper, we study {\it matter-wave pressure} through examining the dynamics of a quantum-classical hybrid system. The quantum ... More
Driving Quantum System into Decoherence-free Subspaces by Lyapunov ControlAug 07 2009We present a scheme to drive a finite-dimensional quantum system into the decoherence-free subspaces(DFS) by Lyapunov control. Control fields are established by Lyapunov function. This proposal works well for both closed and open quantum systems, with ... More
Excitation Spectrum and Collective Modes of Composite FermionsSep 13 1994According to the composite fermion theory, the interacting electron system at filling factor $\nu$ is equivalent to the non-interacting composite fermion system at $\nu^*=\nu/(1-2m\nu)$, which in turn is related to the non-interacting electron system ... More
Hund's Rule for Composite FermionsDec 22 1993We consider the ``fractional quantum Hall atom" in the vanishing Zeeman energy limit, and investigate the validity of Hund's maximum-spin rule for interacting electrons in various Landau levels. While it is not valid for {\em electrons} in the lowest ... More
Electron spin relaxation in GaAs$_{1-x}$Bi$_x$: Effects of spin-orbit tuning by Bi incorporationMay 27 2012The electron spin relaxation in $n$-type and intrinsic GaAs$_{1-x}$Bi$_x$ with Bi composition $0\le x \le 0.1$ is investigated from the microscopic kinetic spin Bloch equation approach. The incorporation of Bi is shown to markedly decrease the spin relaxation ... More
Transport properties in Cu$_{x}$TiSe$_{2}$ (0.015$\leq$x$\leq$0.110) Single CrystalMar 25 2007Transport properties are systematically studied for the single crystals Cu$_{x}$TiSe$_{2}$ (0.015$\leq$x$\leq$0.110). Both of in-plane and out-of-plane resistivity show the coexistence of superconducting transition and charge density wave (CDW) for the ... More
Novel dynamical effects and glassy response in strongly correlated electronic systemMar 25 2007We find an unconventional nucleation of low temperature paramagnetic metal (PMM) phase with monoclinic structure from the matrix of high-temperature antiferromagnetic insulator (AFI) phase with tetragonal structure in strongly correlated electronic system ... More
Electron tunneling through a single magnetic barrier in HgTe topological insulatorJul 20 2016Electron tunneling through a single magnetic barrier in a HgTe topological insulator has been theoretically investigated. We find that the perpendicular magnetic field would not lead to spin-flip of the edge states due to the conservation of the angular ... More
Giant isotope effect and spin state transition induced by oxygen isotope exchange in ($Pr_{1-x}Sm_x)_{0.7}Ca_{0.3}CoO_3$Mar 28 2006Apr 30 2006We systematically investigate effect of oxygen isotope in $(Pr_{1-x}Sm_x)_{0.7}Ca_{0.3}CoO_3$ which shows a crossover with x from ferromagnetic metal to the insulator with spin-state transition. A striking feature is that effect of oxygen isotope on the ... More
Charge ordering in charge-compensated $Na_{0.41}CoO_2$ by oxonium ionsJan 10 2005Dec 20 2005Charge ordering behavior is observed in the crystal prepared through the immersion of the $Na_{0.41}CoO_2$ crystal in distilled water. Discovery of the charge ordering in the crystal with Na content less than 0.5 indicates that the immersion in water ... 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
Metastable giant moments in Gd-implanted GaN, Si, and sapphireMar 28 2011We report on Gd ion implantation and magnetic characterization of GaN films on sapphire substrates and of bare sapphire and Si substrates to shed light on the mechanism underlying the induced magnetism upon Gd ion implantation. For all three hosts, giant ... More
Quantum logic gates and maximally entangled states in microtrapsApr 05 2002Apr 08 2002This paper has been withdrawn because the first author submitted the paper without previously consulting the rest of the authors.
X-Ray Afterglow Plateaus of Long Gamma-Ray Bursts: Further Evidence for Millisecond MagnetarsJan 08 2014Many long-duration gamma-ray bursts (GRBs) were observed by {\it Swift}/XRT to have plateaus in their X-ray afterglow light curves. This plateau phase has been argued to be evidence for long-lasting activity of magnetar (ultra-strongly magnetized neutron ... More
Unusual glitch behaviours of two young pulsarsJul 22 2004In this paper we report unusual glitches in two young pulsars, PSR J1825-0935 (B1822-09) and PSR J1835-1106. For PSR J1825-0935, a slow glitch characterised by a temporary decrease in the slowdown rate occurred between 2000 December 31 to 2001 December ... More
Quantum correlation measure in arbitrary bipartite systemsSep 04 2013Oct 09 2013A definition of quantum correlation is presented for an arbitrary bipartite quantum state based on the skew information. This definition not only inherits the good properties of skew information such as the contractivity and so on, but also is effective ... More
Entanglement of Fermi gases in a harmonic trapOct 27 2005For both cases with and without interactions, bipartite entanglement of two-fermions from a Fermi gas in a trap is investigated. We show how the entanglement depends on the locations of the two fermions and the total number of particles. Fermions at the ... More
Self-optimization of optical confinement in ultraviolet photonic crystal slab laserDec 08 2005We studied numerically and experimentally the effects of structural disorder on the performance of ultraviolet photonic crystal slab lasers. Optical gain selectively amplifies the high-quality modes of the passive system. For these modes, the in-plane ... More
Excitons in two coupled conjugated polymer chainsSep 23 1997We have studied the exciton states in two coupled conjugated polymer chains which are modeled individually by the Su-Schrieffer-Heeger Hamiltonian and coupled by an interchain electron-transfer term. Both the intra- and inter-chain long range Coulomb ... More
Gap solitons and Bloch waves of interacting bosons in one-dimensional optical lattices: From the weak to the strong interaction limitsMar 06 2011We study the gap solitons and nonlinear Bloch waves of interacting bosons in one-dimensional optical lattices, taking into account the interaction from the weak to the strong limits. It is shown that composition relation between the gap solitons and nonlinear ... More
Infrared spectroscopy of the charge ordering transition in Na$_{0.5}$CoO$_2$May 11 2004We report infrared spectra of a Na$_{0.5}$CoO$_2$ single crystal which exhibits a sharp metal-insulator transition near 50 K due to the formation of charge ordering. In comparison with x=0.7 and 0.85 compounds, we found that the spectral weight associated ... More
Influence of doping level on the Hall coefficient and on the thermoelectric power in $Nd_{2-x}Ce_xCuO_4$Jun 25 2005Oct 20 2005Hall coefficient $R_H$ and thermoelectric power TEP are studied systematically in the single crystals $Nd_{2-x}Ce_xCuO_{4+\delta}$ (NCCO) with different x from underdoped to overdoped regime. With increasing doping level, both $R_H$ and TEP decrease and ... More
Two superconducting phases and their characteristics in layered BaTi2(Sb1-xBix)2O with x=0.16May 09 2014Two correlated superconducting phases are identified in layered superconductor BaTi2(Sb1-xBix)2O (x=0.16), with the superconducting transition temperatures of TC = 6 K (the high TC phase) and 3.4 K (the low TC Phase), respectively. The 6 K superconducting ... 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
Strain tuning of optical emission energy and polarization in monolayer and bilayer MoS2Jun 14 2013We use micro-Raman and photoluminescence (PL) spectroscopy at 300K to investigate the influence of uniaxial tensile strain on the vibrational and optoelectronic properties of monolayer and bilayer MoS2 on a flexible substrate. The initially degenerate ... 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
X-Ray Flares from Postmerger Millisecond PulsarsFeb 23 2006Recent observations support the suggestion that short-duration gamma-ray bursts are produced by compact star mergers. The X-ray flares discovered in two short gamma-ray bursts last much longer than the previously proposed postmerger energy release time ... More
High performance current and spin diode of atomic carbon chain between transversely symmetric ribbon electrodesAug 29 2014We demonstrate that giant current and high spin rectification ratios can be achieved in atomic carbon chain devices connected between two symmetric ferromagnetic zigzag-graphene-nanoribbon electrodes. The spin dependent transport simulation is carried ... More
Orbital Period and Outburst Luminosity of Transient Low Mass X-ray BinariesJun 01 2010In this paper we investigate the relation between the maximal luminosity of X-ray outburst and the orbital period in transient low mass X-ray binaries (or soft X-ray transients) observed by the Rossi X-ray Timing Explorer (RXTE) in the past decade. We ... More
Engineering steady Knill-Laflamme-Milburn state of Rydberg atoms by dissipationMar 06 2018The Knill-Laflamme-Milburn (KLM) states have been proved to be a useful resource for quantum information processing [Nature 409, 46 (2001)]. For atomic KLM states, several schemes have been put forward based on the time-dependent unitary dynamics, but ... More
Noise-induced distributed entanglement in atom-cavity-fiber systemMar 06 2018The distributed quantum computation plays an important role in large-scale quantum information processing. In the atom-cavity-fiber system, we put forward two efficient proposals to prepare the steady entanglement of two distant atoms with dissipation. ... More
Spectroscopic Properties of QSOs Selected from Ultraluminous Infrared Galaxy SamplesMar 26 2002We performed spectroscopic observations for a large infrared QSO sample with a total of 25 objects. The sample was compiled from the QDOT redshift survey, the 1 Jy ULIRGs survey and a sample obtained by a cross-correlation study of the IRAS Point Source ... More
Van der Waals trilayers and superlattices: Modification of electronic structures of MoS2 by intercalationMar 13 2014We perform a comprehensive first-principles study of the electronic properties of van der Waals (vdW) trilayers via intercalating a two-dimensional (2D) monolayer (ML = BN, MoSe2, WS2, or WSe2) between MoS2 bilayer to form various MoS2/ML/MoS2 sandwich ... More
Timing measurements and proper motions of 74 pulsars using the Nanshan radio telescopeJun 30 2005Jul 01 2005We have measured the positions of 74 pulsars from regular timing observations using the Nanshan radio telescope at Urumqi Observatory between 2000 January and 2004 August (MJD 51500 -- 53240). Proper motions were determined for these pulsars by comparing ... More
A Two-Component Explosion Model for the Giant Flare and Radio Afterglow from SGR1806-20Jul 14 2005The brightest giant flare from the soft $\gamma$-ray repeater (SGR) 1806-20 was detected on 2004 December 27. The isotropic-equivalent energy release of this burst is at least one order of magnitude more energetic than those of the two other SGR giant ... More
An energetic blast wave from the December 27 giant flare of the soft gamma-ray repeater 1806-20Feb 04 2005Mar 03 2005Recent follow-up observations of the December 27 giant flare of SGR 1806-20 have detected a multiple-frequency radio afterglow from 240 MHz to 8.46 GHz, extending in time from a week to about a month after the flare. The angular size of the source was ... More
Canonical Form and Separability of PPT States in 2xMxN Composite Quantum SystemsDec 03 2003We investigate the canonical forms of positive partial transposition (PPT) density matrices in ${\cal C}^2 \otimes {\cal C}^M \otimes {\cal C}^N$ composite quantum systems with rank $N$. A general expression for these PPT states are explicitly obtained. ... More
Re-Identification of the `Enigmatic' X-ray Source 1RXS J114003.0+124112Feb 21 2006The ROSAT X-ray source 1RXS J114003.0+124112 was identified as a starburst galaxy at redshift 0.177 by He et al. (2001). Meanwhile, the authors also noted that the source is almost two orders of magnitude brighter in X-ray than the X-ray-brightest starburst ... More
Shortcuts to adiabaticity in non-Hermitian quantum systems without rotating-wave approximationOct 14 2017The technique of shortcuts to adiabaticity (STA) has attracted broad attention due to their possible applications in quantum information processing and quantum control. However, most studies published so far have been only focused on Hermitian systems ... More
Coexistence of Superconductivity and Ferromagnetism in Dilute Co-doped $La_{1.89} Ce_{0.11} Cu O_{4\pm\d}$ SystemAug 15 2006Thin films of the optimally electron-doped $T'$-phase superconductor La$_{1.89}$Ce$_{0.11}$CuO$_{4\pm \d}$ are investigated by dilute Co doping, formed as La$_{1.89}$Ce$_{0.11}$(Cu$_{1-x}$Co$_{x}$)O$_{4\pm\d}$ (LCCCO) with $x$ = 0.01 -- 0.05. The following ... More
Skyrmions in the Fractional Quantum Hall EffectApr 03 1996It is verified that, at small Zeeman energies, the charged excitations in the vicinity of 1/3 filled Landau level are skyrmions of composite fermions, analogous to the skyrmions of electrons near filling factor unity. These are found to be relevant, however, ... More
Fermi-liquid effects in the gapless state of marginally thin superconducting filmsSep 24 2008We present low temperature tunneling density-of-states measurements in Al films in high parallel magnetic fields. The thickness range of the films, t=6-9 nm, was chosen so that the orbital and Zeeman contributions to their parallel critical fields were ... More
Absorption-induced confinement of lasing modes in diffusive random mediumApr 18 2005We present a numerical study of lasing modes in diffusive random media with local pumping. The reabsorption of emitted light suppresses the feedback from the unpumped part of the sample and effectively reduces the system size. The lasing modes are dramatically ... More
Exact dynamics of interacting qubits in a thermal environment: Results beyond the weak coupling limitJul 30 2012We demonstrate an exact mapping of a class of models of two interacting qubits in thermal reservoirs to two separate spin-bath problems. Based on this mapping, exact numerical simulations of the qubits dynamics can be performed, beyond the weak system-bath ... More
Nonlinear quantum heat transfer in hybrid structures: Sufficient conditions for thermal rectificationMay 25 2009We present a unified description of heat flow in two-terminal hybrid quantum systems. Using simple models, we analytically study nonlinear aspects of heat transfer between various reservoirs: metals, solids, and spin baths, mediated by the excitation/relaxation ... More