The magnetic-field-tuned superconductor-insulator transition has been studied in ultrathin Beryllium films quench-condensed near 20 K. In the zero-current limit, a finite-size scaling analysis yields the scaling exponent product vz = 1.35 +/- 0.10 and a critical sheet resistance R_{c} of about 1.2R_{Q}, with R_{Q} = h/4e^{2}. However, in the presence of dc bias currents that are smaller than the zero-field critical currents, vz becomes 0.75 +/- 0.10. This new set of exponents suggests that the field-tuned transitions with and without dc bias currents belong to different universality classes.
@article{arxiv.cond-mat/0108232,
title = {The Field-Tuned Superconductor-Insulator Transition with and without Current Bias},
author = {E. Bielejec and Wenhao Wu},
journal= {arXiv preprint arXiv:cond-mat/0108232},
year = {2009}
}
Comments
RevTex 4 pages, 4 figures, and 1 table minor changes