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arXiv · 0707.1271

Sine-Gordon description of Beresinskii-Kosterlitz-Thouless physics at finite magnetic field

L. Benfatto·C. Castellani·T. Giamarchi
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Abstract

The Beresinskii-Kosterlitz-Thouless (BKT) physics of vortices in two-dimensional superconductors at finite magnetic field is investigated by means of a field-theoretical approach based on the sine-Gordon model. This description leads to a straightforward definition of the field-induced magnetization and shows that the persistence of non-linear effects at low fields above the transition is a typical signature of the fast divergence of the correlation length within the BKT theory.

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L. Benfatto, C. Castellani, T. Giamarchi. 2007-10-25. Sine-Gordon description of Beresinskii-Kosterlitz-Thouless physics at finite magnetic field. https://doi.org/10.1103/physrevlett.99.207002

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