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Properties for CD Inequalities with Unbounded LaplaciansDec 08 2015The CD equalities were introduced to imply the gradient estimate of laplace operator on graphs. This article is based on the unbounded Laplacians, and finally concludes some equivalent properties of the CD(K,$\infty$)and CD(K,n).

Recollection: an Alternative Restoration Technique for Constraint Programming SystemsJan 27 2016Feb 04 2016Search is a key service within constraint programming systems, and it demands the restoration of previously accessed states during the exploration of a search tree. Restoration proceeds either bottom-up within the tree to roll back previously performed ... More

Programmable Restoration Granularity in Constraint ProgrammingJan 25 2016Feb 04 2016In most constraint programming systems, a limited number of search engines is offered while the programming of user-customized search algorithms requires low-level efforts, which complicates the deployment of such algorithms. To alleviate this limitation, ... More

Graphs with large girth and nonnegative curvature dimension conditionAug 25 2016In this paper, we classify unweighted graphs satisfying the curvature dimension condition CD(0,\infty) whose girth are at least five.

Stochastic completeness for graphs with curvature dimension conditionsApr 01 2015Aug 09 2015We prove pointwise gradient bounds for heat semigroups associated to general (possibly unbounded) Laplacians on infinite graphs satisfying the curvature dimension condition CD(K,\infty). Using gradient bounds, we show stochastic completeness for graphs ... More

Equivalent Properties of CD Inequality on GraphDec 06 2015We study some equivalent properties of the curvature-dimension conditions $CD(n,K)$ inequality on infinite, but locally finite graph. These equivalences are gradient estimate, Poincar\'e type inequalities and reverse Poincar\'e inequalities. And we also ... More

A brief review on geometry and spectrum of graphsApr 14 2012This is a survey paper. We study the Ricci curvature and spectrum of graphs, as well as the exterior forms and deRahm cohomology on graphs.

Fluctuation-induced tunneling conduction through RuO$_2$ nanowire contactsAug 17 2011A good understanding of the electronic conduction processes through nanocontacts is a crucial step for the implementation of functional nanoelectronic devices. We have studied the current-voltage ($I$-$V$) characteristics of nanocontacts between single ... More

Quantum tunneling on graphsJan 13 2011We explore the tunneling behavior of a quantum particle on a finite graph, in the presence of an asymptotically large potential. Surprisingly the behavior is governed by the local symmetry of the graph around the wells.

Kazdan-Warner equation on graphJul 15 2016Let $G=(V,E)$ be a finite graph and $\Delta$ be the usual graph Laplacian. Using the calculus of variations and a method of upper and lower solutions, we give various conditions such that the Kazdan-Warner equation $\Delta u=c-he^u$ has a solution on ... More

Time-Dependent Variational Principle for $φ^4$ Field Theory: RPA Approximation and Renormalization (II)May 11 1998The Gaussian-time-dependent variational equations are used to explored the physics of $(\phi^4)_{3+1}$ field theory. We have investigated the static solutions and discussed the conditions of renormalization. Using these results and stability analysis ... More

Synthetic spin-orbit coupling in ultracold $Λ$-type atomsJul 23 2012We consider the simulation of non-abelian gauge potentials in ultracold atom systems with atom-field interaction in the $\Lambda$ configuration where two internal states of an atom are coupled to a third common one with a detuning. We find the simulated ... More

Existence of positive solutions to some nonlinear equations on locally finite graphsJul 15 2016Let $G=(V,E)$ be a locally finite graph, whose measure $\mu(x)$ have positive lower bound, and $\Delta$ be the usual graph Laplacian. Applying the mountain-pass theorem due to Ambrosetti-Rabinowitz, we establish existence results for some nonlinear equations, ... More

Global gradient estimate on graph and its applicationsOct 24 2015Continuing our previous work (arXiv:1509.07981v1), we derive another global gradient estimate for positive functions, particularly for positive solutions to the heat equation on finite or locally finite graphs. In general, the gradient estimate in the ... More

Ricci-flat graphs with girth at least fiveJan 01 2013A graph is called Ricci-flat if its Ricci-curvatures vanish on all edges. Here we use the definition of Ricci-cruvature on graphs given in [Lin-Lu-Yau, Tohoku Math., 2011], which is a variation of [Ollivier, J. Funct. Math., 2009]. In this paper, we classified ... More

Quasinormal behavior of massless scalar field perturbation in Reissner-Nordstrom anti-de Sitter spacetimesJul 05 2004Oct 29 2011We present a comprehensive study of the massless scalar field perturbation in the Reissner-Nordstrom anti-de Sitter (RNAdS) spacetime and compute its quasinormal modes (QNM). For the lowest lying mode, we confirm and extend the dependence of the QNM frequencies ... More

S-Lemma with Equality and Its ApplicationsMar 12 2014Apr 17 2015Let $f(x)=x^TAx+2a^Tx+c$ and $h(x)=x^TBx+2b^Tx+d$ be two quadratic functions having symmetric matrices $A$ and $B$. The S-lemma with equality asks when the unsolvability of the system $f(x)<0, h(x)=0$ implies the existence of a real number $\mu$ such ... More

Harnack inequalities for graphs with non-negative Ricci curvatureJul 27 2012We establish a Harnack inequality for finite connected graphs with non-negative Ricci curvature. As a consequence, we derive an eigenvalue lower bound, extending previous results for Ricci flat graphs.

A gradient estimate for positive functions on graphsSep 26 2015We derive a gradient estimate for positive functions, in particular for positive solutions to the heat equation, on finite or locally finite graphs. Unlike the well known Li-Yau estimate, which is based on the maximum principle, our estimate follows from ... More

Ultracontractivity and functional inequalities on infinite graphsFeb 06 2015In this paper, we prove the equivalent of ultracontractive bound of heat semigroup or the uniform upper bound of the heat kernel with the Nash inequality, Log-Sobolev inequalities on graphs. We also show that under the assumption of volume growth and ... More

Anisotropic Weyl Fermions from Quasiparticle Excitation Spectrum of a 3D Fulde-Ferrell SuperfluidOct 15 2013Jul 04 2014Weyl fermions, first proposed for describing massless chiral Dirac fermions in particle physics, have not been observed yet in experiments. Recently, much effort has been devoted to explore Weyl fermions around band touching points of single particle ... More

Local partial-likelihood estimation for lifetime dataMay 18 2006This paper considers a proportional hazards model, which allows one to examine the extent to which covariates interact nonlinearly with an exposure variable, for analysis of lifetime data. A local partial-likelihood technique is proposed to estimate nonlinear ... More

Yamabe type equations on graphsJul 15 2016Let $G=(V,E)$ be a locally finite graph, $\Omega\subset V$ be a bounded domain, $\Delta$ be the usual graph Laplacian, and $\lambda_1(\Omega)$ be the first eigenvalue of $-\Delta$ with respect to Dirichlet boundary condition. Using the mountain pass theorem ... More

Constraints on the interacting holographic dark energy modelSep 14 2005Mar 31 2006We examined the interacting holographic dark energy model in a universe with spatial curvature. Using the near-flatness condition and requiring that the universe is experiencing an accelerated expansion, we have constrained the parameter space of the ... More

Quasinormal modes of Reissner-Nordstr$\ddot{o}$m Anti-de Sitter Black HolesMar 31 2000Complex frequencies associated with quasinormal modes for large Reissner-Nordstr$\ddot{o}$m Anti-de Sitter black holes have been computed. These frequencies have close relation to the black hole charge and do not linearly scale with the black hole temperature ... More

Approximation Algorithms for Link Scheduling with Physical Interference Model in Wireless Multi-hop NetworksOct 27 2009The link scheduling in wireless multi-hop networks is addressed. Different from most of work that adopt the protocol interference model which merely take consideration of packet collisions, our proposed algorithms use the physical interference model to ... More

WMAP constraint on the P-term inflationary modelSep 17 2003Feb 19 2004In light of WMAP results, we examine the observational constraint on the P-term inflation. With the tunable parameter $f$, P-term inflation contains richer physics than D-term and F-term inflationary models. We find the logarithmic derivative spectral ... More

Universal Quantum Degeneracy Point for Superconducting QubitsJan 15 2011The quantum degeneracy point approach [D. Vion et al., Science 296, 886 (2002)] effectively protects superconducting qubits from low-frequency noise that couples with the qubits as transverse noise. However, low-frequency noise in superconducting qubits ... More

A Revisit to Quadratic Programming with One Inequality Quadratic Constraint via Matrix PencilDec 05 2013The quadratic programming over one inequality quadratic constraint (QP1QC) is a very special case of quadratically constrained quadratic programming (QCQP) and attracted much attention since early 1990's. It is now understood that, under the primal Slater ... More

Energy translation and Proper-Time EigenstatesFeb 13 2006Nov 10 2006The usual quantum mechanics describes the mass eigenstates. To describe the proper-time eigenstates, a duality theory of the usual quantum mechanics was developed. The time interval is treated as an operator on an equal footing with the space interval, ... More

Initial-Value Problem for Inhomogeneous Condensate: Gaussian Approximation and BeyondFeb 02 1999Using many-body theory we develop a set of formally exact kinetic equations for inhomogeneous condensate and one-body observables. The method is illutrated for phi^4 field theory in 1+1 dimensions. These equations, when computed with the help of time-dependent ... More

Nonequilibrium Damping of Collective Motion of Homogeneous Cold Fermi Condensates with Feshbach ResonancesJan 10 2012Collisionless damping of a condensate of cold Fermi atoms, whose scattering is controlled by a Feshbach resonance, is explored throughout the BCS and BEC regimes when small perturbations on its phase and amplitude modes are turned on to drive the system ... More

Signature of the black hole phase transition in quasinormal modesFeb 13 2010Apr 05 2010We study the perturbation of the scalar field interacting with the Maxwell field in the background of d-dimensional charged AdS black hole and AdS soliton. Different from the single classical field perturbation, which always has the decay mode in the ... More

Intrinsic anisotropy of thermal conductance in graphene nanoribbonsOct 17 2009Thermal conductance of graphene nanoribbons (GNRs) with the width varying from 0.5 to 35 nm is systematically investigated using nonequilibrium Green's function method. Anisotropic thermal conductance is observed with the room temperature thermal conductance ... More

Double Well Potential Function and Its Optimization in the n-dimensional Real Space - Part IIApr 07 2014In contrast to taking the dual approach for finding a global minimum solution of a double well potential function, in Part II of the paper, we characterize a local minimizer, local maximizer, and global minimizer directly from the primal side. It is proven ... More

Probing charmonium-like state $X(3915)$ through meson photoproductionDec 26 2013Jan 11 2014Inspired by the observation of charmonium-like state $X(3915)$, we explore the discovery potential of the $X(3915)$ production via meson photoproduction process. By investigating the $\gamma p \to J/\psi\omega p$ process including the $X(3915)$ signal ... More

Revisiting the production of charmonium plus a light meson at PANDAMar 19 2012Jul 27 2012In this work, we calculate the total cross sections and the center-of-mass frame angular distributions of the charmonium production plus a light meson by the low energy $p\bar{p}$ interaction. The results of $p\bar{p}\to \pi^0 \Psi$ with and without form ... More

The transition of equation of state of effective dark energy in the DGP model with bulk contentsAug 07 2007Oct 08 2007We investigate the effect of the bulk contents in the DGP braneworld on the evolution of the universe. We find that although the pure DGP model cannot accommodate the transition of the effective equation of state of dark energy, once the bulk matter T^5_5 ... More

An SDP Approach For Solving Quadratic Fractional Programming ProblemsFeb 18 2014This paper considers a fractional programming problem (P) which minimizes a ratio of quadratic functions subject to a two-sided quadratic constraint. As is well-known, the fractional objective function can be replaced by a parametric family of quadratic ... More

Homotopy theory for digraphsJul 01 2014We introduce a homotopy theory of digraphs (directed graphs) and prove its basic properties, including the relations to the homology theory of digraphs constructed by the authors in previous papers. In particular, we prove the homotopy invariance of homologies ... More

Homologies of path complexes and digraphsJul 12 2012May 11 2013In this paper we introduce a path complex that can be regarded as a generalization of the notion of a simplicial complex. The main motivation for considering path complexes comes from directed graphs(digraphs). We obtain a new notion of the path homology ... More

Self-consistent renormalization group flowOct 12 2000A self-consistent renormalization group flow equation for the scalar lambda phi^4 theory is analyzed and compared with the local potential approximation. The two prescriptions coincide in the sharp cutoff limit but differ with a smooth cutoff. The dependence ... More

Quasinormal modes of black holes absorbing dark energyDec 31 2008Feb 04 2009We study perturbations of black holes absorbing dark energy. Due to the accretion of dark energy, the black hole mass changes. We observe distinct perturbation behaviors for absorption of different forms of dark energy into the black holes. This provides ... More

First estimate of producing the charmed baryon $Λ_c(2880)$ at PANDAMar 13 2014Jul 10 2014In the present work we explore the production potential of $\Lambda_c(2880)^+$ at PANDA. With the $J^P=\frac{5}{2}^+$ assignment to $\Lambda_c(2880)^+$, we calculate the differential and total cross sections of $p\bar{p}\to \Lambda_c^-\Lambda_c(2880)^+$. ... More

Charged charmoniumlike state $Z_c(3900)^\pm$ via meson photoproductionAug 29 2013Dec 02 2013In this work, we explore the production of the newly observed charged charmoniumlike state $Z_c(3900)^\pm$ by the photoproduction process $\gamma p\to Z_c(3900)^+n$. Our numerical result indicates that the maximum of the calculated total cross section ... More

On the p-regularized trust region subproblemSep 16 2014The $p$-regularized subproblem (p-RS) is a regularisation technique in computing a Newton-like step for unconstrained optimization, which globally minimizes a local quadratic approximation of the objective function while incorporating with a weighted ... More

Extraspecial Two-Groups, Generalized Yang-Baxter Equations and Braiding Quantum GatesJun 12 2007Aug 30 2010In this paper we describe connections among extraspecial 2-groups, unitary representations of the braid group and multi-qubit braiding quantum gates. We first construct new representations of extraspecial 2-groups. Extending the latter by the symmetric ... More

Charged bottomonium-like states $Z_b(10610)$ and $Z_b(10650)$ and the $Υ(5S)\to Υ(2S)π^+π^-$ decayMay 26 2011Sep 17 2011Inspired by the newly observed two charged bottomonium-like states, we consider the possible contribution from the intermediate $Z_b(10610)$ and $Z_b(10650)$ states to the $\Upsilon(5S)\to \Upsilon(2S)\pi^+\pi^-$ decay process, which naturally explains ... More

Differentially Categorized Structural Connectome Hubs are Involved in Differential Microstructural Basis and Functional Implications and Contribute to Individual IdentificationSep 12 2016Human brain structural networks contain sets of centrally embedded hub regions that enable efficient information communication. However, it remains largely unknown about categories of structural brain hubs and their microstructural, functional and cognitive ... More

Volume doubling, Poincaré inequality and Guassian heat kernel estimate for nonnegative curvature graphsNov 19 2014Dec 06 2015By studying the heat semigroup, we prove Li-Yau type estimates for bounded and positive solutions of the heat equation on graphs, under the assumption of the curvature-dimension inequality $CDE'(n,0)$, which can be consider as a notion of curvature for ... More

Nodal geometry of graphs on surfacesJul 11 2013We prove two mixed versions of the Discrete Nodal Theorem of Davies et. al. [3] for bounded degree graphs, and for three-connected graphs of fixed genus $g$. Using this we can show that for a three-connected graph satisfying a certain volume-growth condition, ... More

Measurements of plasma motions in dynamic fibrilsOct 04 2007We present a 40 minute time series of filtergrams from the red and the blue wing of the \halpha line in an active region near the solar disk center. From these filtergrams we construct both Dopplergrams and summed ``line center'' images. Several dynamic ... More

Spontaneous Vortex Production in Driven Condensates with Narrow Feshbach ResonancesAug 28 2009Jul 21 2011We explore the possibility that, at zero temperature, vortices can be created spontaneously in a condensate of cold Fermi atoms, whose scattering is controlled by a narrow Feshbach resonance, by rapid magnetic tuning from the BEC to BCS regime. This could ... More

ZBroker: A Query Routing Broker for Z39.50 DatabasesFeb 09 1999A query routing broker is a software agent that determines from a large set of accessing information sources the ones most relevant to a user's information need. As the number of information sources on the Internet increases dramatically, future users ... More

Studying Frequency Relations of kHz QPOs for 4U 1636-53 and Sco X-1: Observations Confront TheoriesOct 29 2010By fitting the frequencies of simultaneous lower and upper kilohertz Quasi-Periodic Oscillations (kHz QPOs) in two prototype neutron star QPO sources (4U~1636-536 and Sco X-1), we test the predictive power of all currently proposed QPO models. Models ... More

Derivation of hydrodynamics for the gapless mode in the BEC-BCS crossover from the exact one-loop effective actionJun 09 2006Dec 11 2006We show that many hydrodynamical properties of the BEC/BCS crossover in the presence of a Feshbach resonance at T=0 can be derived easily from the derivative expansion of the (exact) fully renormalized one-loop effective action. In particular, we calculate ... More

Thermodynamical description of the interaction between holographic dark energy and dark matterNov 14 2007Feb 15 2008We present a thermodynamical description of the interaction between holographic dark energy and dark matter. If holographic dark energy and dark matter evolve separately, each of them remains in thermodynamic equilibrium. A small interaction between them ... More

The Non-universal behaviour of Cold Fermi Condensates with Narrow Feshbach ResonancesOct 10 2008Jul 30 2009In this paper we construct an effective field theory for a condensate of cold Fermi atoms whose scattering is controlled by a narrow Feshbach resonance. We show how, from first principles, it permits a hydrodynamic description of the BEC-BCS crossover ... More

A scheme for tunable quantum phase gate and effective preparation of graph-state entanglementJan 07 2008A scheme is presented for realizing a quantum phase gate with three-level atoms, solid-state qubits--often called artificial atoms, or ions that share a quantum data bus such as a single mode field in cavity QED system or a collective vibrational state ... More

Direct Observation of Long-Term Durability of Superconductivity in YBa$_2$Cu$_3$O$_7$-Ag$_2$O CompositesJul 09 2003We report direct observation of long-term durability of superconductivity of several YBa$_2$Cu$_3$O$_7$-Ag$_2$O composites that were first prepared and studied almost 14 years ago [J. J. Lin {\it et al}., Jpn. J. Appl. Phys. {\bf 29}, 497 (1990)]. Remeasurements ... More

Observation of fluctuation-induced tunneling conduction in micrometer-sized tunnel junctionsAug 15 2012Micrometer-sized Al/AlO$_{x}$/Y tunnel junctions were fabricated by the electron-beam lithography technique. The thin ($\approx$ 1.5--2 nm thickness) insulating AlO$_{x}$ layer was grown on top of the Al base electrode by O$_{2}$ glow discharge. The zero-bias ... More

Frequency-up conversion and quantum swap gate in an optical cavity with atomic cloudJan 05 2008A scheme is presented for realizing frequency-up conversion and a two-qubit quantum swap gate for intracavity fields. In the scheme, a V-type atomic ensemble prepared in their ground states collectively mediates the interaction between the two cavity ... More

The First Infrared Telescope in Tibet Plateau, ChinaJun 19 2012We plan to install an infrared telescope at the new site of Tibet, China. The primary mirror diameter is 50cm, and the focal ratio F8. The Xenics 640\times512 near infrared camera is employed, equipped with a dedicated high speed InGaAs detector array, ... More

Multifractality and Laplace spectrum of horizontal visibility graphs constructed from fractional Brownian motionsFeb 17 2016Many studies have shown that additional information can be gained on time series by investigating their associated complex networks. In this work, we investigate the multifractal property and Laplace spectrum of the horizontal visibility graphs (HVGs) ... More

Photon Production from Nonequilibrium Disoriented Chiral Condensates in a Spherical ExpansionAug 25 2002Oct 04 2002We study the production of photons through the non-equilibrium relaxation of a disoriented chiral condensate formed in the expanding hot central region in ultra-relativistic heavy-ion collisions. It is found that the expansion smoothes out the resonances ... More

Stability of the warped black string with nontrivial topology in five-dimensional Anti-de Sitter spacetimeApr 24 2010Aug 17 2010We investigate the stability of a new warped black string with nontrivial topologies in five-dimensional Anti-de Sitter spacetime. After studying the linear gravitational perturbation, we find that this black string is unstable when the Kaluza-Klein mass ... More

A new Gross-Pitaevskii action for cold Fermi condensatesSep 18 2016The BEC regime of a cold fermi gas is characterised by coupled atoms (dimers) which, superficially, look very much like elementary bosons. We construct a new Gross-Pitaevskii action for the BEC regime in which dimers are represented by coupled fields, ... More

Exploring triad-rich substructures by graph-theoretic characterizations in complex networksFeb 17 2016One of the most important problems in complex networks is how to detect metadata groups accurately. The main challenge lies in the fact that traditional structural communities do not always capture the intrinsic features of metadata groups. Motivated ... More

Interplay between Quantum Size Effect and Strain Effect on Growth of Nanoscale Metal Thin FilmAug 30 2012We develop a theoretical framework to investigate the interplay between quantum size effect (QSE) and strain effect on the stability of metal nanofilms. The QSE and strain effect are shown to be coupled through the concept of "quantum electronic stress. ... More

Storing light as a mechanical excitation in a silica optomechanical resonatorJun 22 2011We report the experimental demonstration of optomechanical light storage in a silica resonator. We use writing and readout laser pulses tuned to one mechanical frequency below an optical cavity resonance to control the coupling between the mechanical ... More

A unified approach for exactly solvable potentials in quantum mechanics using shift operatorsAug 01 2000We present a unified approach for solving and classifying exactly solvable potentials. Our unified approach encompasses many well-known exactly solvable potentials. Moreover, the new approach can be used to search systematically for a new class of solvable ... More

Dissipative optomechanics of a single-layer graphene in a microcavityNov 09 2014Nov 11 2014We study the optomechanical coupling of a single-layer graphene with a high-Q Fabry-Perot microcavity in the membrane-in-the-middle configuration. In ordinary dissipative coupling systems, mechanical oscillators modulate the loss associated with the input ... More

Network analyzer measurements of spin transfer torques in magnetic tunnel junctionsMar 30 2012Jul 24 2012We demonstrate a simple network-analyzer technique to make quantitative measurements of the bias dependence of spin torque in a magnetic tunnel junction. We apply a microwave current to exert an oscillating spin torque near the ferromagnetic resonance ... More

Quasinormal modes in the background of charged Kaluza-Klein black hole with squashed horizonsFeb 18 2008Jun 17 2008We study the scalar perturbation in the background of the charged Kaluza-Klein black holes with squashed horizons. We find that the position of infinite discontinuities of the heat capacities can be reflected in quasinormal spectrum. This shows the possible ... More

Fermion Pairing Dynamics in the Relativistic Scalar PlasmaMay 11 1998Jul 23 1999Using many-body techniques we obtain the time-dependent Gaussian approximation for interacting fermion-scalar field models. This method is applied to an uniform system of relativistic spin-1/2 fermion field coupled, through a Yukawa term, to a scalar ... More

Elementary excitations of a Higgs-Yukawa systemApr 02 2013This work investigates the physics of elementary excitations for the so-called relativistic quantum scalar plasma system, also known as the Higgs-Yukawa system. Following the Nemes-Piza-Kerman-Lin many-body procedure, the Random-Phase Approximation (RPA) ... More

Elementary Excitations of a Relativistic Scalar Plasma SystemFeb 01 1999We investigate the physics of elementary excitations for the so called relativistic scalar plasma system. Following the standard many-body procedure we have obtained the RPA equations for this model by linearizing the TDHFB equations of motion around ... More

Generation of atomic entangled states in a bi-mode cavity via adiabatic passageApr 29 2009We propose schemes to prepare atomic entangled states in a bi-mode cavity via stimulated Raman adiabatic passage (STIRAP) and fractional stimulated Raman adiabatic passage (f-STIRAP) tech- niques. According to the simulation results, our schemes keep ... More

Proportion of frozen local polarization in relaxor ferroelectricsMar 01 2001A Landau-type phenomenological cluster theory was presented to model the freezing process of local polarization in relaxors. Based on the theory, the proportion of frozen polarization in Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_3$-PbTiO$_3$ (PMNT) was calculated from ... More

Simultaneous Integer Relation Detection and Its an ApplicationJun 26 2009Jan 25 2010Let $\mathbf{x_1}, ..., \mathbf{x_t} \in \mathbb{R}^{n}$. A simultaneous integer relation (SIR) for $\mathbf{x_1}, ..., \mathbf{x_t}$ is a vector $\mathbf{m} \in \mathbb{Z}^{n}\setminus\{\textbf{0}\}$ such that $\mathbf{x_i}^T\mathbf{m} = 0$ for $i = ... More

Deposition of quantum dots in a capillary tubeNov 18 2015The ability to assemble nanomaterials, such as quantum dots, enables the creation of functional devices that present unique optical and electronic properties. For instance, light-emitting diodes with exceptional color purity can be printed via the evaporative-driven ... More

Exploration of nonlocalities in ensembles consisting of bipartite quantum statesJan 12 2009Aug 31 2010It is revealed that ensembles consisting of multipartite quantum states can exhibit different kinds of nonlocalities. An operational measure is introduced to quantify nonlocalities in ensembles consisting of bipartite quantum states. Various upper and ... More

Orbital density wave induced by electron-lattice coupling in orthorhombic iron pnictidesApr 23 2011In this paper we explore the magnetic and orbital properties closely related to a tetragonal-orthorhombic structural phase transition in iron pnictides based on both two- and five-orbital Hubbard models. The electron-lattice coupling, which interplays ... More

Higher bottom and bottom-strange mesonsJan 08 2014Mar 21 2014Motivated by the recent observation of the orbital excitation $B(5970)$ by CDF collaboration, we have performed a systematical study of the mass spectrum and strong decay patterns of the higher $B$ and $B_s$ mesons. Hopefully the present investigation ... More

Determination of the superconducting gap in near optimally doped Bi_2Sr_{2-x}La_xCuO_{6+δ} (x ~ 0.4) from low-temperature specific heatFeb 28 2011Low-temperature specific heat of the monolayer high-Tc superconductor Bi_2Sr_{2-x}La_xCuO_{6+\delta} has been measured close to the optimal doping point (x ~ 0.4) in different magnetic fields. The identification of both a T^2 term in zero field and a ... More

Ricci-flat cubic graphs with girth fiveFeb 08 2018We classify all connected, simple, 3-regular graphs with girth at least 5 that are Ricci-flat. We use the definition of Ricci curvature on graphs given in Lin-Lu-Yau, Tohoku Math., 2011, which is a variation of Ollivier, J. Funct. Anal., 2009. A graph ... More

Measurement of mass by optical forced oscillation of absorbing particles trapped in airJan 16 2017We demonstrate the measurement of mass of the absorbing micro-particle trapped in air by optical forced oscillation. When the trapping light intensity is modulated sinusoidally, the particle in the trap undergoes forced oscillation and the amplitude of ... More

Longitudinal Single Bunch Instability Study on BEPCIIApr 10 2013In order to study the single bunch longitudinal instability in BEPCII, experiments on the positron ring (BPR) for the bunch lengthening phenomenon were made. By analyzing the experimental data based on Gao's theory, the longitudinal loss factor for the ... More

Robust Recovery of Subspace Structures by Low-Rank RepresentationOct 14 2010May 06 2012In this work we address the subspace recovery problem. Given a set of data samples (vectors) approximately drawn from a union of multiple subspaces, our goal is to segment the samples into their respective subspaces and correct the possible errors as ... More

Interacting Dark Energy and Dark Matter: observational Constraints from Cosmological ParametersJul 07 2006May 02 2007Several observational constraints are imposed on the interacting holographic model of Dark Energy and Dark Matter. First we use the age parameter today, as given by the WMAP results. Subsequently, we explained the reason why it is possible, as recently ... More

Time-Dependent Variational Analysis of Josephson Oscillations in a Two-component Bose-Einstein CondensateDec 13 1999The dynamics of Josephson-like oscillations between two coupled Bose-Einstein condensates is studied using the time-dependent variational method. We suppose that the quantum state of the condensates is a gaussian wave-packet which can translate and perform ... More

Doorway states and the Bose-Hubbard modelOct 05 2005Nov 07 2010We introduce an efficient method to solve the Mott-Hubbard model. The Schr\"{o}dinger equation is solved by the successive construction of doorway states. The ground state wavefunction derived by this method contains all relevant many-body correlations ... More

Collective Excitation of a Hybrid Atomic/Molecular Bose Einstein Condensate$^{\ast}$Nov 16 1999The collective excitation of hybrid atomic-molecular condensate are studied using variational method. The dipole response of the system is studied in detail. We found that the out-of-phase dipole oscillation frequency increasing slowly with the detuning ... More

Quantum stochastic behaviour in cold Fermi gases: Phonon propagationFeb 26 2014Feb 03 2015We examine the effect of quantum fluctuations in a tunable cold Fermi gas on the propagation of phonons. We show that these fluctuations can be interpreted as inducing a stochastic (acoustic) space-time. The variation in times of flight induced by this ... More

Functionalized Germanene as a Prototype of Large-Gap Two-Dimensional Topological InsulatorsJan 16 2014We propose new two-dimensional (2D) topological insulators (TIs) in functionalized germanenes (GeX, X=H, F, Cl, Br or I) using first-principles calculations. We find GeI is a 2D TI with a bulk gap of about 0.3 eV, while GeH, GeF, GeCl and GeBr can be ... More

Dirac semimetal phase in the hexagonal LiZnBiMar 20 2016Based on first-principles calculations, we find that LiZnBi, a metallic hexagonal $ABC$ compound, can be driven into a Dirac semimetal with a pair of Dirac points by strain. The nontrivial topological nature of the strained LiZnBi is directly demonstrated ... More

Effect of Exchange-type Zero-bias Anomaly on Single Electron Tunnelling of Au NanoparticlesJun 14 2011Using cryogenic scanning tunnelling microscopy and scanning tunnelling spectroscopy we measured single electron tunnelling of isolated Au nanoparticles with 1.4 nm in radius. We observe that a gap {\Delta}V ~ 2e/C (C is the capacitance of the Au particle) ... More

The role of Causality in Tunable Fermi Gas CondensatesMay 01 2012Sep 17 2013We develop a new formalism for the description of the condensates of cold Fermi atoms whose speed of sound can be tuned with the aid of a narrow Feshbach resonance. We use this to look for spontaneous phonon creation that mimics spontaneous particle creation ... More

Preparation of magnetic tips for spin-polarized STM on Fe_{1+y}TeNov 07 2014The interplay of electronic nematic modulations, magnetic order, superconductivity and structural distortions in strongly correlated electron materials calls for methods which allow characterizing them simultaneously - to allow establishing directly the ... More

Physical accessible transformations on a finite number of quantum statesNov 09 2006We consider to treat the usual probabilistic cloning, state separation, unambiguous state discrimination, \emph{etc} in a uniform framework. All these transformations can be regarded as special examples of generalized completely positive trace non-increasing ... More