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arXiv · 1702.05930

Broadening of the Berezinskii-Kosterlitz-Thouless transition by correlated disorder

I. Maccari·L. Benfatto·C. Castellani
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Abstract

The Berezinskii-Kosterlitz-Thouless (BKT) transition in two-dimensional superconductors is usually expected to be protected against disorder. However, its typical signatures in real system, like e.g. the superfluid-density jump, are often at odd with this expectation. Here we show that the disorder-induced granularity of the superconducting state modifies the nucleation mechanism for vortex-antivortex pairs. This leads to a considerable smearing of the universal superfluid-density jump as compared to the paradigmatic clean case, in agreement with experimental observations.

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I. Maccari, L. Benfatto, C. Castellani. 2017-02-20. Broadening of the Berezinskii-Kosterlitz-Thouless transition by correlated disorder. https://doi.org/10.1103/physrevb.96.060508

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