396 research outputs found
Monte Carlo Simulations of Vector Spin Glasses at Low Temperatures
In this paper I report results for simulations of the three-dimensional gauge
glass and the four-dimensional XY spin glass using the parallel tempering Monte
Carlo method at low temperatures for moderate sizes. The results are
qualitatively consistent with earlier work on the three- and four-dimensional
Edwards-Anderson Ising spin glass. I find evidence that large-scale excitations
may cost only a finite amount of energy in the thermodynamic limit. The surface
of these excitations is fractal, but I cannot rule out for the XY spin glass a
scenario compatible with replica symmetry breaking where the surface of
low-energy large-scale excitations is space filling.Comment: Proceedings of "Computational Modeling and Simulation of Complex
Systems" Conference 2001, Aachen, Germany, September 5 - 8, 2001. 4 pages, 6
figure
Temperature and Disorder Chaos in Three-Dimensional Ising Spin Glasses
We study the effects of small temperature as well as disorder perturbations
on the equilibrium state of three-dimensional Ising spin glasses via an
alternate scaling ansatz. By using Monte Carlo simulations, we show that
temperature and disorder perturbations yield chaotic changes in the equilibrium
state and that temperature chaos is considerably harder to observe than
disorder chaos.Comment: 4 pages, 3 figures, 1 tabl
Casimir Force between two Half Spaces of Vortex Matter in Anisotropic Superconductors
We present a new approach to calculate the attractive long-range
vortex-vortex interaction of the van der Waals type present in anisotropic and
layered superconductors. The mapping of the statistical mechanics of
two-dimensional charged bosons allows us to define a Casimir problem: Two half
spaces of vortex matter separated by a gap of width R are mapped to two
dielectric half planes of charged bosons interacting via a massive gauge field.
We determine the attractive Casimir force between the two half planes and show
that it agrees with the pairwise summation of the van der Waals force between
vortices.Comment: Submitted to Physica C (4 pages, 2 figures
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