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 ϵr 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/4e2 and the crossover thickness close to 25 A˚ 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.
@article{arxiv.cond-mat/0209027,
title = {Insulator superconductor transition on solid inert gas substrates},
author = {K. Das Gupta and Swati S. Soman and G. Sambandamurthy and N. Chandrasekhar},
journal= {arXiv preprint arXiv:cond-mat/0209027},
year = {2009}
}