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Insulator superconductor transition on solid inert gas substrates

K. Das Gupta·Swati S. Soman·G. Sambandamurthy·N. Chandrasekhar
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Abstract

We present observations of the insulator-superconductor transition in ultrathin films of Bi on solid xenon condensed on quartz and on Ge on quartz. The relative permeability $ε_{r}$ ranges from 1.5 for Xe to 15 for Ge. Though we find screening effects as expected, the I-S transition is robust, and unmodified by the substrate. The resistance separatrix is found to be close to $h/4e^2$ and the crossover thickness close to 25 $Å$ for all substrates. I-V studies and Aslamazov-Larkin analyses indicate superconductivity is inhomogeneous. The transition is best described in terms of a percolation model.

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K. Das Gupta, Swati S. Soman, G. Sambandamurthy, N. Chandrasekhar. 2002-09-02. Insulator superconductor transition on solid inert gas substrates. https://doi.org/10.1016/s0921-4526(02)02259-7

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