Scale dependent superconductor-insulator transition

D. Kowal; Z. Ovadyahu

doi:10.1016/j.physc.2007.07.012

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arXiv · 0708.2751

Scale dependent superconductor-insulator transition

D. Kowal·Z. Ovadyahu

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Abstract

We study the disorder driven superconductor to insulator transition in amorphous films of high carrier-concentration indium-oxide. Using thin films with various sizes and aspect ratios we show that the `critical' sheet-resistance $R_{\small \square}$ depends systematically on sample geometry; superconductivity disappears when $R_{\small \square}$ exceeds $\approx6 $k$Ω$ in large samples. On the other hand, wide and sufficiently short samples of the same batch exhibit superconductivity (judged by conductivity versus temperature) up to $R_{\small \square}$ which is considerably larger. These results support the inhomogeneous scenario for the superconductor-insulator transition.

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BibTeX RIS

D. Kowal, Z. Ovadyahu. 2007-08-21. Scale dependent superconductor-insulator transition. https://doi.org/10.1016/j.physc.2007.07.012

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