Non-linear $IV$ characteristics in two-dimensional superconductors: Berezinskii-Kosterlitz-Thouless physics vs inhomogeneity
Abstract
One of the hallmarks of the Berezinskii-Kosterlitz-Thouless (BKT) transition in two-dimensional (2D) superconductors is the universal jump of the superfluid density, that can be indirectly probed via the non-linear exponent of the current-voltage characteristics. Here, we compare the experimental measurements of characteristics in two cases, namely NbN thin films and SrTiO-based interfaces. While the former display a paradigmatic example of BKT-like non-linear effects, the latter do not seem to justify a BKT analysis. Rather, the observed characteristics can be well reproduced theoretically by modelling the effect of mesoscopic inhomogeneity of the superconducting state. Our results offer an alternative perspective on the spontaneous fragmentation of the superconducting background in confined 2D systems.
Keywords
Cite
@article{arxiv.1905.01221,
title = {Non-linear $IV$ characteristics in two-dimensional superconductors: Berezinskii-Kosterlitz-Thouless physics vs inhomogeneity},
author = {G. Venditti and J. Biscaras and S. Hurand and N. Bergeal and J. Lesueur and A. Dogra and R. C. Budhani and Mintu Mondal and John Jesudasan and Pratap Raychaudhuri and S. Caprara and L. Benfatto},
journal= {arXiv preprint arXiv:1905.01221},
year = {2019}
}
Comments
Final version, as published