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arXiv · 0812.1793

Investigating superconductor-insulator transition in thin films using drag resistance:Theoretical analysis of a proposed experiment

Yue Zou·Gil Refael·Jongsoo Yoon
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Abstract

The magnetically driven superconductor-insulator transition in amorphous thin films (e.g., InO, Ta) exhibits several mysterious phenomena, such as a putative metallic phase and a huge magnetoresistance peak. Unfortunately, several conflicting categories of theories, particularly quantum-vortex condensation, and normal region percolation, explain key observations equally well. We propose a new experimental setup, an amorphous thin-film bilayer, where a drag resistance measurement would clarify the role quantum vortices play in the transition, and hence decisively point to the correct picture. We provide a thorough analysis of the device, which shows that the vortex paradigm gives rise to a drag with an opposite sign and orders of magnitude larger than the drag measured if competing paradigms apply.

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Yue Zou, Gil Refael, Jongsoo Yoon. 2009-11-07. Investigating superconductor-insulator transition in thin films using drag resistance:Theoretical analysis of a proposed experiment. https://doi.org/10.1103/physrevb.80.180503

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