108,340 research outputs found

    Fraunhofer diffraction at the two-dimensional quadratically distorted (QD) Grating

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    A two-dimensional (2D) mathematical model of quadratically distorted (QD) grating is established with the principles of Fraunhofer diffraction and Fourier optics. Discrete sampling and bisection algorithm are applied for finding numerical solution of the diffraction pattern of QD grating. This 2D mathematical model allows the precise design of QD grating and improves the optical performance of simultaneous multiplane imaging system.Comment: 4 pages, 6 figure

    Gradient Estimate on the Neumann Semigroup and Applications

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    We prove the following sharp upper bound for the gradient of the Neumann semigroup PtP_t on a dd-dimensional compact domain \OO with boundary either C2C^2-smooth or convex: \|\nn P_t\|_{1\to \infty}\le \ff{c}{t^{(d+1)/2}},\ \ t>0, where c>0c>0 is a constant depending on the domain and 1\|\cdot\|_{1\to\infty} is the operator norm from L^1(\OO) to L^\infty(\OO). This estimate implies a Gaussian type point-wise upper bound for the gradient of the Neumann heat kernel, which is applied to the study of the Hardy spaces, Riesz transforms, and regularity of solutions to the inhomogeneous Neumann problem on compact convex domains

    Inequalities of Hermite-Hadamard type for extended ss-convex functions and applications to means

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    In the paper, the authors introduce a new concept "extended ss-convex functions", establish some new integral inequalities of Hermite-Hadamard type for this kind of functions, and apply these inequalities to derive some inequalities of special means.Comment: 17 page

    Half-arc-transitive graphs of prime-cube order of small valencies

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    A graph is called {\em half-arc-transitive} if its full automorphism group acts transitively on vertices and edges, but not on arcs. It is well known that for any prime pp there is no tetravalent half-arc-transitive graph of order pp or p2p^2. Xu~[Half-transitive graphs of prime-cube order, J. Algebraic Combin. 1 (1992) 275-282] classified half-arc-transitive graphs of order p3p^3 and valency 44. In this paper we classify half-arc-transitive graphs of order p3p^3 and valency 66 or 88. In particular, the first known infinite family of half-arc-transitive Cayley graphs on non-metacyclic pp-groups is constructed.Comment: 13 page

    A new example of limit variety of aperiodic monoids

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    A limit variety is a variety that is minimal with respect to being non-finitely based. The two limit varieties of Marcel Jackson are the only known examples of limit varieties of aperiodic monoids. Our previous work had shown that there exists a limit subvariety of aperiodic monoids that is different from Marcel Jackson's limit varieties. In this paper, we introduce a new limit variety of aperiodic monoids.Comment: 16 pages, 1 figur

    Rapid heating and cooling in two-dimensional Yukawa systems

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    Simulations are reported to investigate solid superheating and liquid supercooling of two-dimensional (2D) systems with a Yukawa interparticle potential. Motivated by experiments where a dusty plasma is heated and then cooled suddenly, we track particle motion using a simulation with Langevin dynamics. Hysteresis is observed when the temperature is varied rapidly in a heating and cooling cycle. As in the experiment, transient solid superheating, but not liquid supercooling, is observed. Solid superheating, which is characterized by solid structure above the melting point, is found to be promoted by a higher rate of temperature increase.Comment: 7 pages, 5 figure

    Effect of interaction strength on the evolution of cooperation

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    Cooperative behaviors are ubiquitous in nature,which is a puzzle to evolutionary biology,because the defector always gains more benefit than the cooperator,thus,the cooperator should decrease and vanish over time.This typical "prisoners' dilemma" phenomenon has been widely researched in recent years.The interaction strength between cooperators and defectors is introduced in this paper(in human society,it can be understood as the tolerance of cooperators).We find that only when the maximum interaction strength is between two critical values,the cooperator and defector can coexist,otherwise, 1) if it is greater than the upper value,the cooperator will vanish, 2) if it is less than the lower value,a bistable state will appear

    Probabilistic Dense Coding Using Non-Maximally Entangled Three-Particle State

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    We present a scheme of probabilistic dense coding via a quantum channel of non-maximally entangled three-particle state. The quantum dense coding will be succeeded with a certain probability if the sender introduces an auxiliary particle and performs a collective unitary transformation. Furthermore, the average information transmitted in this scheme is calculated.Comment: 4 page

    Electron correlation and impurity-induced quasiparticle resonance states in cuprate superconductors

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    We theoretically study the quasiparticle resonance states around a nonmagnetic impurity in cuprate superconductors based on t-t'-J-U model. The purpose of introducing the Coulomb repulsive interaction U is to partially impose the double occupancy constraint by employing the Gutzwiller projected mean-field approximation. We determine the spatial variation of the order parameter and the local density of states (LDOS) by self-consistently solving Bogoliubov-de Gennes equations. We find that in the large U limit, a zero-energy resonance peak in the LDOS indeed appears for the impurity potential in the unitary limit, at the same time the asymmetric superconducting coherence peaks are strongly suppressed. As U decreases the electron double occupancy d is permitted and gradually increases, leading to the decreasing of order parameter. In particular the above zero-energy resonance peak begins to evolve into a double-peaked structure since a critical value dcd_{c}. These important feathers are qualitatively agreement with the scanning tunneling spectroscopy experiments, and uncover the essential role played by the electron correlation in cuprate superconductors.Comment: 5 pages, 5 figure

    On the minimal affinizations over the quantum affine algebras of type CnC_n

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    In this paper, we study the minimal affinizations over the quantum affine algebras of type CnC_n by using the theory of cluster algebras. We show that the qq-characters of a large family of minimal affinizations of type CnC_n satisfy some systems of equations. These equations correspond to mutation equations of some cluster algebras. Furthermore, we show that the minimal affinizations in these equations correspond to cluster variables in these cluster algebras.Comment: arXiv admin note: substantial text overlap with arXiv:1501.00146, arXiv:1502.0242
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