Results for "Q. Niu"

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Screening, nonadiabaticity, and quantized acoustoelectric currentSep 13 1999Nov 05 1999Quantized single-electron transport driven by surface acoustic waves (SAW) through a pinched-off narrow constriction is studied theoretically. Long-range Coulomb interaction causes the tunneling coupling between the two-dimensional electron gas (2DEG) ... More
Vortex Dynamics in Superfluid Systems: Cyclotron Type MotionApr 02 1996Vortex dynamics in superfluids is investigated in the framework of the nonlinear Schr\"{o}dinger equation. The natural motion of the vortex is of cyclotron type, whose frequency is found to be on the order of phonon velocity divided by the coherence length, ... More
From Feynman's Wave Function to the Effective Theory of Vortex DynamicsJan 21 1994We calculate the overlap between two many-body wave functions for a superfluid film containing a vortex at shifted positions. Comparing the results to phenomenological theories, which treat vortices as point particles, we find that the results are consistent ... More
Dynamic Fractional Stark Ladders in DC--AC FieldsDec 09 1993Dec 09 1994A single band in a spatially periodic system splits into a series of quasienergy subbands under the action of DC--AC electric fields. These dynamic fractional Stark ladders should be observable in an investigation of optical absorption.
Coordinate shift in the semiclassical Boltzmann equation and the anomalous Hall effectNov 12 2005Jan 27 2006We propose a gauge invariant expression for the side jump associated with scattering between particular Bloch states. Our expression for the side jump follows from the Born series expansion for the scattering T-matrix in powers of the strength of the ... More
Waltzing of a Helium Pair in Tungsten: Migration Barrier and Trajectory Revealed from First-PrinciplesApr 18 2014Despite well documented first-principles theoretical determination of the low migration energy (0.06 eV) of a single He in tungsten, fully quantum mechanical calculations on the migration of a He pair still present a challenge due to the complexity of ... More
Quantized Density Response in InsulatorsMar 18 1994The response of particle density to a dilation of a periodic potential in an insulator, with or without a fixed background potential or a magnetic field, is shown to be quantized. A similar phenomenon occurs in a quantum Hall system, where the derivative ... More
Measurements of a fast nuclear spin dynamics in a single InAs quantum dot with positively charged excitonJan 05 2012By using highly time-resolved spectroscopy with an alternative {\sigma}+/{\sigma} - laser pulse modulation technique, we are able to measure the fast buildup and decay times of the dynamical nuclear spin polarization (DNSP) at 5 K for a single InAs quantum ... More
Non-vanishing spin Hall currents in disordered spin-orbit coupling systemsJul 11 2004Nov 24 2004Spin currents that flow perpendicular to the electric field direction are generic in metals and doped semiconductors with spin-orbit coupling. It has recently been argued that the spin Hall conductivity can be dominated by an intrinsic contribution which ... More
Strong photon blockade with intracavity electromagnetically induced transparency in blockaded Rydberg ensembleAug 13 2013Dec 14 2015We consider the dynamics of intracavity electromagnetically induced transparency (EIT) in an ensemble of strongly interacting Rydberg atoms. By combining the advantage of variable cavity lifetimes with intracavity EIT and strongly interacting Rydberg ... More
Global dynamical correlation energies in covariant density functional theory: cranking approximationMay 08 2013Jan 20 2014The global dynamical correlation energies for 575 even-even nuclei with proton numbers ranging from Z=8 to Z=108 calculated with the covariant density functional theory using the PC-PK1 parametrization are presented. The dynamical correlation energies ... More
Tunable ultranarrow linewidth of cavity induced by interacting dark resonancesJun 17 2009A scheme for getting a tunable ultranarrow linewidth of a cavity due to an embedded four-level atomic medium with double-dark resonances is proposed. It is shown that the steep dispersion induced by double-dark resonances in the transparency window leads ... More
Aharonov-Bohm and Aharonov-Casher Effects: Connections to Dynamics of Topological SingularitiesMar 10 1998We analyze the physical processes involved in the Aharonov-Bohm (A-B) and the Aharonov-Casher (A-C) effects, showing that an incomplete A-B effect knowledge can lead a totally wrong conclusion on the A-C effect. Based on this we demonstrate that the Magnus ... More
Tellurene-a monolayer of tellurium from first-principles predictionMay 11 2016A two dimensional (2D) Group-VI Te monolayer, tellurene, is predicted by using the first-principles calculations, which consists of planner four-membered and chair-like six-membered rings arranged alternately in a 2D lattice. The phonon spectra calculations, ... More
Berry phase, hyperorbits, and the Hofstadter spectrumMay 04 1995We develop a semiclassical theory for the dynamics of electrons in a magnetic Bloch band, where the Berry phase plays an important role. This theory, together with the Boltzmann equation, provides a framework for studying transport problems in high magnetic ... More
Local Density of States and Level Width for Wannier-Stark LaddersJul 21 1993The local density of states \rho(x,E) is calculated for a Bloch electron in an electric field. Depending on the system size, we can see one or more sequences of Wannier-Stark ladders in \rho(x,E), with Lorentz type level widths and apparent spatial localization ... More
Electron Band Structure in a Two Dimensional Periodic Magnetic FieldJul 19 1994In this paper we study the energy spectrum of a two dimensional electron gas (2DEG) in a two dimensional periodic magnetic field. Both a square magnetic lattice and a triangular one are considered. We consider the general case where the magnetic field ... More
Berry phase, hyperorbits, and the Hofstadter spectrum: semiclassical dynamics in magnetic Bloch bandsNov 02 1995We have derived a new set of semiclassical equations for electrons in magnetic Bloch bands. The velocity and energy of magnetic Bloch electrons are found to be modified by the Berry phase and magnetization. This semiclassical approach is used to study ... More
Quantum Nondemolition Measurement and Heralded Preparation of Fock States with Electromagnetically Induced Transparency in an Optical CavityMar 01 2012Mar 29 2012We propose a technique for quantum nondemolition (QND) measurement and heralded preparation of Fock states by dynamics of electromagnetically induced transparency (EIT). An atomic ensemble trapped in an optical cavity is driven by two external continuous-wave ... More
Ultrabroadband photosensitivity from visible to terahertz at room temperatureJun 23 2018Charge-density wave (CDW) is one of the most fundamental quantum phenomena in solids. Different from ordinary metals in which only single particle excitations exist, CDW also has collective excitations and can carry electric current in a collective fashion. ... More
Some Results on Asymptotic Regularity of Ideal SheavesJun 14 2011Let $\mathscr{I}$ be an ideal sheaf on $P^n$ defining a subscheme $X$. Associated to $\mathscr{I}$ there are two elementary invariants: the invariant $s$ which measures the positivity of $\mathscr{I}$, and the minimal number $d$ such that $\mathscr{I}(d)$ ... More
A Bound for the Castelnuovo-Mumford Regularity of Log Canonical VarietiesDec 17 2009Feb 01 2011In this note, we give a bound for the Castelnuovo-Mumford regularity of a homogeneous ideal $I$ in terms of the degrees of its generators. We assume that $I$ defines a local complete intersection with log canonical singularities.
Codimension-two Bifurcations Induce Hysteresis Behavior and Multistabilities in Delay-coupled Kuramoto OscillatorsAug 11 2016Hysteresis phenomena and multistability play crucial roles in the dynamics of coupled oscillators, which are now interpreted from the point of view of codimension-two bifurcations. On the Ott-Antonsen's manifold, complete bifurcation sets of delay-coupled ... More
Anomalous Nernst and Hall effects in magnetized platinum and palladiumJun 04 2014We study the anomalous Nernst effect (ANE) and anomalous Hall effect (AHE) in proximity-induced ferromagnetic palladium and platinum which is widely used in spintronics, within the Berry phase formalism based on the relativistic band structure calculations. ... More
Quasilinear quantum magnetoresistance in pressure-induced nonsymmorphic superconductor CrAsDec 22 2016In conventional metals, modification of electron trajectories under magnetic field gives rise to a magnetoresistance that varies quadratically at low field, followed by a saturation at high field for closed orbits on the Fermi surface. Deviations from ... More
Pumping in an interacting quantum wireJun 06 2003We study charge and spin pumping in an interacting one-dimensional wire. We show that a spatially periodic potential modulated in space and time acts as a quantum pump inducing a dc-current component at zero bias. The current generated by the pump is ... More
Derivation of the transverse force on a moving vortex in a superfluidAug 20 1996We describe an exact derivation of the total nondissipative transverse force acting on a quantized vortex moving in a uniform background. The derivation is valid for neutral boson or fermion superfluids, provided the order parameter is a complex scalar ... More
Interactions of Collective Excitations with Vortices in Superfluid SystemsDec 26 1994We investigate the interactions of collective excitations with vortices in superfluid systems, including $~^4$He and superconductors. The dynamical equations are obtained by the aid of the many-body wavefunction and the density-density correlation function. ... More
Transverse force on a quantized vortex in a superfluidMar 30 1996We have derived an exact expression for the total nondissipative transverse force acting on a quantized vortex moving in a uniform background. The derivation is valid for neutral boson or fermion superfluids, provided the order parameter is a complex ... More
From Feynman's Wave Function to the Effective Theory of Vortex DynamicsJan 21 1994We calculate the overlap between two many-body wave functions for a superfluid film containing a vortex at shifted positions. Comparing the results to phenomenological theories, which treat vortices as point particles, we find that the results are consistent ... More
Controllable spin-orbit coupling and its influence on the upper critical field in the chemically doped quasi-one-dimensional Nb$_2$PdS$_5$ superconductorSep 30 2014By systematic chemical substitution of Pt and Ni in the newly-discovered superconductor Nb$_2$PdS$_5$ ($T_c\sim$6 K), we study the evolution of its superconducting properties with doping, focussing on the behavior of the upper critical field $H_{c2}$. ... 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
Tracing crystal-field splittings in the rare earth-based intermetallic CeIrIn$_5$Feb 13 2018Crystal electric field states in rare earth intermetallics show an intricate entanglement with the many-body physics that occurs in these systems and that is known to lead to a plethora of electronic phases. Here, we attempt to trace different contributions ... More
Nuclear effective charge factor originating from covariant density functional theoryMay 24 2013Guiding by the relativistic local density approximation, we explore a phenomenological formula for the coupling strength of Coulomb field to take into account the Coulomb exchange term effectively in the relativistic Hartree approximation. Its validity ... More
Nuclear $β^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairingMay 23 2013Self-consistent proton-neutron quasiparticle random phase approximation based on the spherical nonlinear point-coupling relativistic Hartree-Bogoliubov theory is established and used to investigate the $\beta^+$/EC-decay half-lives of neutron-deficient ... More
Double-tip STM for Surface AnalysisMay 13 1994Dec 26 1994We explore the possibility of using a double-tip STM to probe the single electron Green function of a sample surface, and describe a few important applications: (1) Probing constant energy surfaces in $\k$-space by ballistic transport; (2) Measuring scattering ... More
Effect of Selenium doping on the superconductivity of Nb$_2$Pd(S$_{1-x}$Se$_x$)$_5$Jul 08 2013We study the isovalent substitution effect by partially introducing Se on S site in the newly discovered superconductor Nb$_2$PdS$_5$ ($T_c\sim$6 K) whose upper critical field is found to be far above its Pauli paramagnetic limit. In this Nb$_2$Pd(S$_{1-x}$Se$_x$)$_5$ ... More
Darboux transformations for supersymmetric two-boson equationOct 24 2017In this paper we construct Darboux transformations for the supersymmetric Two-boson equation. Two Darboux transformations and associated B\"acklund transformations are presented. For one of them, we also obtain the corresponding the nonlinear superposition ... More
Adversarial Over-Sensitivity and Over-Stability Strategies for Dialogue ModelsSep 06 2018We present two categories of model-agnostic adversarial strategies that reveal the weaknesses of several generative, task-oriented dialogue models: Should-Not-Change strategies that evaluate over-sensitivity to small and semantics-preserving edits, as ... More
Geometric optics of Bloch waves in a chiral and dissipative mediumApr 13 2009Apr 01 2010We present a geometric optics theory for the transport of quantum particles (or classical waves) in a chiral and dissipative periodic crystal subject to slowly varying perturbations in space and time. Taking account of some properties of particles and ... More
Geometrodynamics of electrons in a crystal under position and time dependent deformationFeb 06 2018Semiclassical dynamics of Bloch electrons in a crystal under slowly varying deformation is developed in the geometric language of a lattice bundle. Berry curvatures and gradients of energy are introduced in terms of lattice covariant derivatives, with ... More
Convergence Rates in Almost-Periodic Homogenization of Higher-order Elliptic SystemsDec 05 2017This paper concentrates on the quantitative homogenization of higher-order elliptic systems with almost-periodic coefficients in bounded Lipschitz domains. For coefficients which are almost-periodic in the sense of H. Weyl, we establish uniform ocal $L^2$ ... More
Uniform Boundary Estimates in Homogenization of Higher Order Elliptic SystemsSep 13 2017This paper focuses on the uniform boundary estimates in homogenization of a family of higher order elliptic operators $\mathcal{L}_\epsilon$, with rapidly oscillating periodic coefficients. We derive uniform boundary $C^{m-1,\lambda} (0\!<\!\lambda\!<\!1)$, ... More
Constraining the non-Einsteinian polarizations of gravitational waves by pulsar timing arrayDec 01 2018Dec 04 2018Pulsar timing array (PTA) provides an excellent opportunity to detect the gravitational waves (GWs) in nanoHertz frequency band. In particular, due to the larger number of "arms" in PTA, it can be used to test gravity by probing the non-Einsteinian polarization ... More
Asymptotic unitary equivalence in $C^*$-algebrasJun 28 2012Aug 11 2013Let $C=C(X)$ be the unital $C^*$-algebra of all continuous functions on a finite CW complex $X$ and let $A$ be a unital simple $C^*$-algebra with tracial rank at most one. We show that two unital monomorphisms $\phi, \psi: C\to A$ are asymptotically unitarily ... More
Quantization and Corrections of Adiabatic Particle Transport in a Periodic Ratchet PotentialJan 08 2002Aug 13 2002We study the transport of an overdamped particle adiabatically driven by an asymmetric potential which is periodic in both space and time. We develop an adiabatic perturbation theory after transforming the Fokker-Planck equation into a time-dependent ... More
Schauder estimates for solutions of sub-Laplace equations with Dini termsFeb 28 2014In this paper we establish Schauder estimates for the sublalpace equation \[\Sigma_{j = 1}^mX_j^2u = f,\] where ${X_1},{X_2}, \ldots ,{X_m}$ is a system of smooth vector field which generates the first layer in the Lie algebra of a Carnot group. We drive ... More
A harmonic Lanczos bidiagonalization method for computing interior singular triplets of large matricesJan 19 2010This paper proposes a harmonic Lanczos bidiagonalization method for computing some interior singular triplets of large matrices. It is shown that the approximate singular triplets are convergent if a certain Rayleigh quotient matrix is uniformly bounded ... More
Weak Field Phase Diagram for an Integer Quantum Hall LiquidApr 04 1995We study the localization properties in the transition from a two-dimensional electron gas at zero magnetic field into an integer quantum Hall (QH) liquid. By carrying out a direct calculation of the localization length for a finite size sample using ... More
A Refined Harmonic Lanczos Bidiagonalization Method and an Implicitly Restarted Algorithm for Computing the Smallest Singular Triplets of Large MatricesJun 12 2009The harmonic Lanczos bidiagonalization method can be used to compute the smallest singular triplets of a large matrix $A$. We prove that for good enough projection subspaces harmonic Ritz values converge if the columns of $A$ are strongly linearly independent. ... More
A tracially AF algebra which is not $\mathcal Z$-absorbingFeb 08 2019Feb 28 2019We show that there is a simple separable unital (non-nuclear) tracially AF algebra $A$ which does not absorb the Jiang-Su algebra $\mathcal Z$ tensorially, i.e. $A \ncong A\otimes\mathcal Z$.
Lower Bounds for Enumerative Counts of Positive-Genus Real CurvesNov 06 2015We transform the positive-genus real Gromov-Witten invariants of many real-orientable symplectic threefolds into signed counts of curves. These integer invariants provide lower bounds for counts of real curves of a given genus that pass through conjugate ... More
Hankel Determinant Calculus for the Thue-Morse and related sequencesJun 06 2014The Hankel determinants of certain automatic sequences $f$ are evaluated, based on a calculation modulo a prime number. In most cases, the Hankel determinants of automatic sequences do not have any closed-form expressions; the traditional methods, such ... More
Extraordinary quasiparticle scattering and bandwidth-control by dopants in iron-based superconductorsApr 27 2014The diversities in crystal structures and ways of doping result in extremely diversified phase diagrams for iron-based superconductors. With angle-resolved photoemission spectroscopy (ARPES), we have systematically studied the effects of chemical substitution ... More
Yet another generalization of Postnikov's hook length formula for binary treesApr 27 2008We discover another one-parameter generalization of Postnikov's hook length formula for binary trees. The particularity of our formula is that the hook length $h_v$ appears as an exponent. As an application, we derive another simple hook length formula ... More
Higher gradients estimates in Morrey spaces for weak solutions to linear ultraparabolic equationsApr 25 2014The aim of this paper is to consider the linear ultraparabolic equation with bounded and VMO coefficients $a_{ij} (z)$. Assume that the operator $L_0$ obtained by freezing the coefficients $a_{ij}(z)$ at any point ${z_0} \in {\mathbb{R}^{N + 1}}$ is hypoelliptic. ... More
An Investigation Report on Auction Mechanism DesignApr 08 2009Apr 14 2009Auctions are markets with strict regulations governing the information available to traders in the market and the possible actions they can take. Since well designed auctions achieve desirable economic outcomes, they have been widely used in solving real-world ... More
A robust adaptive-to-model enhancement test for parametric single-index modelsOct 12 2015In the research on checking whether the underlying model is of parametric single-index structure with outliers in observations, the purpose of this paper is two-fold. First, a test that is robust against outliers is suggested. The Hampel's second-order ... More
Shape evolutions of $^{72,74}$Kr with temperature in the covariant density functional theoryAug 19 2016May 12 2017The rich phenomena of deformations in neutron-deficient krypton isotopes such as the shape evolution with neutron number and the shape coexistence attract the interests of nuclear physicists for decades. It will be interesting to study such shape phenomena ... More
Boundedness of solutions in impulsive Duffing equations with polynomial potentials and $C^{1}$ time dependent coefficientsJun 18 2017In this paper, we are concerned with the impulsive Duffing equation $$ x''+x^{2n+1}+\sum_{i=0}^{2n}x^{i}p_{i}(t)=0,\ t\neq t_{j}, $$ with impulsive effects $x(t_{j}+)=x(t_{j}-),\ x'(t_{j}+)=-x'(t_{j}-),\ j=\pm1,\pm2,\cdots$, where the time dependent coefficients ... More
The effect of the incident relative phase on the four-wave mixing field and the electromagnetically induced transparencyJun 08 2004Aug 11 2004In a Lambda-type system employing a two-photon pump field, a four-wave mixing field can be generated simultaneously and hence a closed-loop system forms. We study theoretically on the effect of the relative phase between the two incident fields on the ... More
Discovering hook length formulas by expansion techniqueMay 16 2008We introduce the hook length expansion technique and explain how to discover old and new hook length formulas for partitions and plane trees. The new hook length formulas for trees obtained by our method can be proved rather easily, whereas those for ... More
$(1^3+1)(2^3+1)\cdots(n^3+1)$ is not a cubeDec 24 2016For a positive integer $n,$ define $$C_n=\prod_{k=1}^n(k^3+1).$$ In this paper we prove that there are no cubes in the integer sequence $C_n,~n=1,2,\cdots.$
Attractive electron-electron interaction induced by geometric phase in a Bloch bandJan 24 2006Nov 21 2006We investigate electron pairing in the presence of the Berry curvature field that ubiquitously exists in ferromagnetic metals with spin-orbit coupling. We show that a sufficiently strong Berry curvature field on the Fermi surface can transform a repulsive ... More
Hankel continued fraction and its applicationsJun 06 2014The Hankel determinants of a given power series $f$ can be evaluated by using the Jacobi continued fraction expansion of $f$. However the existence of the Jacobi continued fraction needs that all Hankel determinants of $f$ are nonzero. We introduce {\it ... More
On Difference-of-SOS and Difference-of-Convex-SOS Decompositions for PolynomialsMar 27 2018Sep 15 2018In this paper, we are interested in difference-of-convex (DC) decompositions of polynomials. We investigate polynomial decomposition techniques for reformulating any multivariate polynomial into difference-of-sums-of-squares (DSOS) and difference-of-convex-sums-of-squares ... More
Existence of optimizers of the Stein-Weiss inequalities on Carnot groupsFeb 28 2014This paper proves existence of optimizers of the Stein-Weiss inequalities on Carnot groups under some conditions. The adjustment of Lions' concentration compactness principles to Carnot groups plays an important role in our proof. Unlike known treatment ... More
Band dependent inter-layer $f$-electron hybridization in CeRhIn$_5$Jan 23 2018A key issue in heavy fermion research is how subtle changes in the hybridization between the 4$f$ (5$f$) and conduction electrons can result in fundamentally different ground states. CeRhIn$_5$ stands out as a particularly notable example: replacing Rh ... More
Temperature dependence of electron-spin relaxation in a single InAs quantum dot at zero applied magnetic fieldJan 05 2012The temperature-dependent electron spin relaxation of positively charged excitons in a single InAs quantum dot (QD) was measured by time-resolved photoluminescence spectroscopy at zero applied magnetic fields. The experimental results show that the electron-spin ... More
Emergence and stability of spontaneous vortex lattices in exciton-polariton condensatesJan 10 2019Jan 11 2019The spontaneous formation of lattice structure of quantized vortices is a characteristic feature of superfluidity in closed systems under thermal equilibrium. In exciton-polariton Bose-Einstein condensate, which is a typical example of macroscopic quantum ... More
Direct observation of how the heavy fermion state develops in CeCoIn5Oct 21 2016Heavy fermion materials gain high electronic masses and expand Fermi surfaces when the high-temperature localized f electrons become itinerant and hybridize with the conduction band at low temperatures. However, despite the common application of this ... More
A breakthrough in Speech emotion recognition using Deep Retinal Convolution Neural NetworksJul 12 2017Speech emotion recognition (SER) is to study the formation and change of speaker's emotional state from the speech signal perspective, so as to make the interaction between human and computer more intelligent. SER is a challenging task that has encountered ... More
Specializations and Extensions of the quantum MacMahon Master TheoremMar 19 2006We study some specializations and extensions of the quantum version of the MacMahon Master Theorem derived by Garoufalidis, Le and Zeilberger. In particular, we obtain a (t,q)-analogue for the Cartier-Foata noncommutative version and a semi-strong (t,q)-analogue ... More
Explicit evaluations of the Hankel determinants of a Thue--Morse-like sequenceJun 06 2014We obtain the explicit evaluations of the Hankel determinants of the formal power series $\prod_{k\geq 0}(1+Jx^{3^{k}})$ where $J={(\sqrt{-3}-1)}/2$, and prove that the sequence of Hankel determinants is an aperiodic automatic sequence taking value in ... More
Particle-vibration coupling effect on the $β$-decay of magic nucleiFeb 17 2015Nuclear $\beta$-decay in magic nuclei is investigated, taking into account the coupling between particle and collective vibrations,on top of self-consistent random phase approximation calculations based on Skyrme density functionals. The low-lying Gamow-Teller ... More
Difference operators for partitions and some applicationsAug 04 2015Jan 18 2018Motivated by the Nekrasov-Okounkov formula on hook lengths, the first author conjectured that the Plancherel average of the $2k$-th power sum of hook lengths of partitions with size $n$ is always a polynomial of $n$ for any $k\in \mathbb{N}$. This conjecture ... More
Some useful theorems for asymptotic formulas and their applications to skew plane partitions and cylindric partitionsJul 16 2017Inspired by the works of Dewar, Murty and Kot\v{e}\v{s}ovec, we establish some useful theorems for asymptotic formulas. As an application, we obtain asymptotic formulas for the numbers of skew plane partitions and cylindric partitions. We prove that the ... More
Galactic cosmic-ray model in the light of AMS-02 nuclei dataMay 30 2017Jan 24 2018Cosmic ray (CR) physics has entered a precision-driven era. With the latest AMS-02 nuclei data (boron-to-carbon ratio, proton flux, helium flux and antiproton-to-proton ratio), we perform a global fitting and constrain the primary source and propagation ... More
Polynomiality of certain average weights for oscillating tableauxSep 02 2017We prove that a family of average weights for oscillating tableaux are polynomials in two variables, namely, the length of the oscillating tableau and the size of the ending partition, which generalizes a result of Hopkins and Zhang. Several explicit ... More
Fix-Mahonian Calculus, II: further statisticsMar 04 2007Using classical transformations on the symmetric group and two transformations constructed in Fix-Mahonian Calculus I, we show that several multivariable statistics are equidistributed either with the triplet (fix,des,maj), or the pair (fix,maj), where ... More
Secant Tree CalculusApr 09 2013A true Tree Calculus is being developed to make a joint study of the two statistics "eoc" (end of minimal chain) and "pom" (parent of maximum leaf) on the set of secant trees. Their joint distribution restricted to the set {eoc-pom<= 1} is shown to satisfy ... More
Finite Difference Calculus for Alternating PermutationsApr 09 2013The finite difference equation system introduced by Christiane Poupard in the study of tangent trees is reinterpreted in the alternating permutation environment. It makes it possible to make a joint study of both tangent and secant trees and calculate ... More
Computer assisted proof for Apwenian sequences related to Hankel determinantsJan 18 2016An infinite $\pm 1$-sequence is called {\it Apwenian} if its Hankel determinant of order $n$ divided by $2^{n-1}$ is an odd number for every positive integer $n$. In 1998, Allouche, Peyri\`ere, Wen and Wen discovered and proved that the Thue--Morse sequence ... More
Skew ribbon plane partitions: calculus and asymptoticsJul 18 2017Plane partitions have been widely studied in Mathematics since MacMahon. See, for example, the works by Andrews, Macdonald, Stanley, Sagan and Krattenthaler. The Schur process approach, introduced by Okounkov and Reshetikhin, and further developed by ... More
New hook-content formulas for strict partitionsNov 09 2015Dec 13 2016We introduce the difference operator for functions defined on strict partitions and prove a polynomiality property for a summation involving the hook length and content statistics. As an application, several new hook-content formulas for strict partitions ... More
Tree Calculus for Bivariable Difference EquationsApr 09 2013Following Poupard's study of strictly ordered binary trees with respect to two parameters, namely, "end of minimal chain" and "parent of maximum leaf" a true Tree Calculus is being developed to solve a partial difference equation system and then make ... More
A combinatorial proof of the non-vanishing of Hankel determinants of the Thue--Morse sequenceJun 06 2014In 1998, Allouche, Peyri\`ere, Wen and Wen established that the Hankel determinants associated with the Thue--Morse sequence on $\{-1, 1\}$ are always nonzero. Their proof depends on a set of sixteen recurrence relations. We present an alternative, purely ... More
Rate-Compatible Punctured Polar Codes: Optimal Construction Based on Polar SpectraDec 05 2016Polar codes are the first class of constructive channel codes achieving the symmetric capacity of the binary-input discrete memoryless channels. But the corresponding code length is limited to the power of two. In this paper, we establish a systematic ... More
Rate-Compatible Punctured Polar Codes: Optimal Construction Based on Polar SpectraDec 05 2016Dec 03 2017Polar codes are the first class of constructive channel codes achieving the symmetric capacity of the binary-input discrete memoryless channels. But the corresponding code length is limited to the power of two. In this paper, we establish a systematic ... More
Systematic calculations of $α$-decay half-lives with an improved empirical formulaMar 05 2015Based on the recent data in NUBASE2012, an improved empirical formula for evaluating the $\alpha$-decay half-lives is presented, in which the hindrance effect resulted from the change of the ground state spins and parities of parent and daughter nuclei ... More
Cavity linewidth narrowing with dark-state polaritonsAug 14 2013Apr 09 2015We perform a quantum-theoretical treatment of cavity linewidth narrowing with intracavity electromagnetically induced transparency (EIT). By means of intracavity EIT, the photons in the cavity are in the form of cavity polaritons: bright-state polariton ... More
Semiclassical theory of spin transport in spin-orbit coupled systemsSep 19 2003Aug 02 2004Motivated by recent interest in novel spintronics effects, we develop a semiclassical theory of spin transport that is valid for spin-orbit coupled bands. Aside from the obvious convective term in which the average spin is transported at the wavepacket ... More
The Edge-State Theory of Integer-Quantum-Hall-Effect to Insulator TransitionAug 28 2000Direct transitions, driven by disorder, from several integral quantum Hall states to an insulator have been observed in experiment. This finding is enigmatic in light of a theoretical phase diagram, based on rather general considerations, that predicts ... More
Surface electronic structure and isotropic superconducting gap in (Li$_{0.8}$Fe$_{0.2}$)OHFeSeJun 09 2015Using angle-resolved photoemission spectroscopy (ARPES), we revealed the surface electronic structure and superconducting gap of (Li$_{0.8}$Fe$_{0.2}$)OHFeSe, an intercalated FeSe-derived superconductor without antiferromagnetic phase or Fe-vacancy order ... More
Universal Intrinsic Spin-Hall EffectJul 27 2003Feb 08 2004We describe a new effect in semiconductor spintronics that leads to dissipationless spin-currents in paramagnetic spin-orbit coupled systems. We argue that in a high mobility two-dimensional electron system with substantial Rashba spin-orbit coupling, ... More
Precise determination of stellar parameters of the ZZ Ceti and DAZ white dwarf GD 133 through asteroseismologyApr 16 2019An increasing number of white dwarf stars show atmospheric chemical composition polluted by heavy elements accreted from debris disk material. The existence of such debris disks strongly suggests the presence of one or more planet(s) whose gravitational ... More
Study $ω$ and $φ$ photoproduction in the nucleon isotopic channelsFeb 07 2002We present results for the photoproduction of $\omega$ and $\phi$ meson in the nucleon isotopic channles. A recently developed quark model with an effective Lagrangian is employed to account for the non-diffractive {\it s}- and {\it u}-channel processes; ... More
$η^\prime$ photoproduction near thresholdNov 19 2000In this work, the $\eta^\prime$ meson photoproduction near threshold is studied in the quark model framework. A pseudovector effective Lagrangian is introduced for the $\eta^\prime NN$ coupling and the newly published data from the SAPHIR Collaboration ... More
Effective Dynamic Range in Measurements with Flash Analog-to-Digital ConvertorApr 14 2003Flash Analog to Digital Convertor (FADC) is frequently used in nuclear and particle physics experiments, often as the major component in big multi-channel systems. The large data volume makes the optimization of operating parameters necessary. This article ... More
Nucleonic resonance excitations and "missing resonances" in the $ω$ meson photoproductionSep 22 1999In this work, an improved quark model approach to the $\omega$ meson photoproduction with an effective Lagrangian is reported. The {\it t}-channel {\it natural} parity exchange is consistently taken into account through the Pomeron exchange, while the ... More