Evidence for a universal minimum superfluid response in field-tuned disordered superconducting films measured using low frequency ac conductivity
Abstract
Our measurements of the low frequency ac conductivity in strongly disordered two-dimensional films near the magnetic field-tuned superconductor-to-insulator transition show a sudden drop in the phase stiffness of superconducting order with either increased temperature or magnetic field. Surprisingly, for two different material systems, the abrupt drop in the superfluid density in a magnetic field has the same universal value as that expected for a Berezinskii-Kosterlitz-Thouless transition in zero magnetic field. The characteristic temperature at which phase stiffness is suddenly lost can be tuned to zero at a critical magnetic field, following a power-law behavior with a critical exponent consistent with that obtained in previous dc transport studies on the dissipative side of the transition.
Keywords
Cite
@article{arxiv.1212.1204,
title = {Evidence for a universal minimum superfluid response in field-tuned disordered superconducting films measured using low frequency ac conductivity},
author = {Shashank Misra and Lukas Urban and Minsoo Kim and Ganapathy Sambandamurthy and Ali Yazdani},
journal= {arXiv preprint arXiv:1212.1204},
year = {2012}
}
Comments
Accepted to Physical Review Letters