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arXiv · 1204.3333

Superconductor Insulator Transition in Long MoGe Nanowires

Hyunjeong Kim·Shirin Jamali·A. Rogachev
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Abstract

Properties of one-dimensional superconducting wires depend on physical processes with different characteristic lengths. To identify the process dominant in the critical regime we have studied trans- port properties of very narrow (9-20 nm) MoGe wires fabricated by advanced electron-beam lithography in wide range of lengths, 1-25 microns. We observed that the wires undergo a superconductor -insulator transition that is controlled by cross sectional area of a wire and possibly also by the thickness-to-width ratio. Mean-field critical temperature decreases exponentially with the inverse of the wire cross section. We observed that qualitatively similar superconductor{insulator transition can be induced by external magnetic field. Some of our long superconducting MoGe nanowires can be identified as localized superconductors, namely in these wires one-electron localization length is much shorter than the length of a wire.

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Hyunjeong Kim, Shirin Jamali, A. Rogachev. 2012-04-15. Superconductor Insulator Transition in Long MoGe Nanowires. https://doi.org/10.1103/physrevlett.109.027002

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