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arXiv · 1006.3793

Dynamical conductivity at the dirty superconductor-metal quantum phase transition

Adrian Del Maestro·Bernd Rosenow·J. A. Hoyos·Thomas Vojta
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Abstract

We study the transport properties of ultrathin disordered nanowires in the neighborhood of the superconductor-metal quantum phase transition. To this end we combine numerical calculations with analytical strong-disorder renormalization group results. The quantum critical conductivity at zero temperature diverges logarithmically as a function of frequency. In the metallic phase, it obeys activated scaling associated with an infinite-randomness quantum critical point. We extend the scaling theory to higher dimensions and discuss implications for experiments.

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Adrian Del Maestro, Bernd Rosenow, J. A. Hoyos, Thomas Vojta. 2010-10-06. Dynamical conductivity at the dirty superconductor-metal quantum phase transition. https://doi.org/10.1103/physrevlett.105.145702

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