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arXiv · cond-mat/9608115

New Universality Class at the Superconductor--Insulator Transition

Karl-Heinz Wagenblast·Anne van Otterlo·Gerd Schön·Gergely T. Zimányi
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Abstract

We study dynamic properties of thin films near the superconductor - insulator transition. We formulate the problem in a phase representation. The key new feature of our model is the assumption of a {\it local} ohmic dissipative mechanism. Coarse graining leads to a Ginzburg-Landau description, with non-ohmic dynamics for the order parameter. For strong enough damping a new universality class is observed. It is characterized by a {\it non-universal} d.c. conductivity, and a damping dependent dynamical critical exponent. The formulation also provides a description of the magnetic field-tuned transition. Several microscopic mechanisms are proposed as the origin of the dissipation.

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Karl-Heinz Wagenblast, Anne van Otterlo, Gerd Schön, Gergely T. Zimányi. 1996-08-24. New Universality Class at the Superconductor--Insulator Transition. https://doi.org/10.1103/physrevlett.78.1779

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