Numerical study of random superconductors
نویسندگان
چکیده
The XY model with quenched random disorder is studied numerically at T 1⁄4 0 by a defect scaling method as a model of a disordered superconductor. In 3D we find that, in the absence of screening, a vortex glass phase exists at low T for large disorder in 3D with stiffness exponent h þ0:31 and with finite screening and in 2D this phase does not exist. For weak disorder, a superconducting phase exists which we identify as a Bragg glass. In the presence of screened vortex– vortex interactions, the vortex glass does not exist but the Bragg glass does. 2004 Elsevier B.V. All rights reserved.
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