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arXiv · 1408.3673

Destruction of superconductivity in disordered materials : a dimensional crossover

O. Crauste·F. Couëdo·L. Bergé·C. A. Marrache-Kikuchi·L. Dumoulin
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Abstract

The disorder-induced Superconductor-to-Insulator Transition in amorphous Nb$_{x}$Si$_{1-x}$ two-dimensional thin films is studied for different niobium compositions $x$ through a variation of the sample thickness $d$. We show that the critical thickness $d_c$, separating a superconducting regime from an insulating one, increases strongly with diminishing $x$, thus attaining values of over 100 {\AA}. The corresponding phase diagram in the $(d, x)$ plane is inferred and related to the three-dimensional situation. The two-dimensional Superconductor-to-Insulator Transition well connects with the three-dimensional Superconductor-to-Metal Transition.

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O. Crauste, F. Couëdo, L. Bergé, C. A. Marrache-Kikuchi, L. Dumoulin. 2014-08-15. Destruction of superconductivity in disordered materials : a dimensional crossover. https://doi.org/10.1103/physrevb.90.060203

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