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The Field-Tuned Superconductor-Insulator Transition with and without Current Bias

E. Bielejec·Wenhao Wu
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Abstract

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.

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E. Bielejec, Wenhao Wu. 2001-10-30. The Field-Tuned Superconductor-Insulator Transition with and without Current Bias. https://doi.org/10.1103/physrevlett.88.206802

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