2,039 research outputs found
Flux-lattice melting in LaOFFeAs: first-principles prediction
We report the theoretical study of the flux-lattice melting in the novel
iron-based superconductor and
. Using the Hypernetted-Chain closure and an
efficient algorithm, we calculate the two-dimensional one-component plasma pair
distribution functions, static structure factors and direct correlation
functions at various temperatures. The Hansen-Verlet freezing criterion is
shown to be valid for vortex-liquid freezing in type-II superconductors.
Flux-lattice meting lines for and
are predicted through the combination of the density
functional theory and the mean-field substrate approach.Comment: 5 pages, 4 figures, to appear in Phys. Rev.
A Feasible Algorithm for Designing Biorthogonal Bivariate Vector-valued Finitely Supported Wavelets
AbstractWavelet analysis has been developed a new branch for over twenty years. The concept of vector-valued binary wavelets with two-scale dilation factor associated with an orthogonal vector-valued scaling function is introduced. The existence of orthogonal vector-valued wavelets with two-scale is discussed. A necessary and sufficient condition is provided by means of vector-valued multiresolution analysis and paraunitary vector filter bank theory. An algorithm for constructing a sort of orthogonal vector-valued wavelets with compact support is proposed, and their orthogonal properties are investigated
Phase transition in site-diluted Josephson junction arrays: A numerical study
We numerically investigate the intriguing effects produced by random
percolative disorder in two-dimensional Josephson-junction arrays. By dynamic
scaling analysis, we evaluate critical temperatures and critical exponents with
high accuracy. It is observed that, with the introduction of site-diluted
disorder, the Kosterlitz-Thouless phase transition is eliminated and evolves
into a continuous transition with power-law divergent correlation length.
Moreover, genuine depinning transition and creep motion are studied, evidence
for distinct creep motion types is provided. Our results not only are in good
agreement with the recent experimental findings, but also shed some light on
the relevant phase transitions.Comment: 7 pages, 8 figures, Phys. Rev. B (in press
Dynamics of glass phases in the two-dimensional gauge glass model
Large-scale simulations have been performed on the current-driven
two-dimensional XY gauge glass model with resistively-shunted-junction
dynamics. It is observed that the linear resistivity at low temperatures tends
to zero, providing strong evidence of glass transition at finite temperature.
Dynamic scaling analysis demonstrates that perfect collapses of current-voltage
data can be achieved with the glass transition temperature , the
correlation length critical exponent , and the dynamic critical
exponent . A genuine continuous depinning transition is found at zero
temperature. For creeping at low temperatures, critical exponents are evaluated
and a non-Arrhenius creep motion is observed in the glass phase.Comment: 10 pages, 6 figure
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