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arXiv · 1406.7510

Evidence for a Finite Temperature Insulator

M. Ovadia·D. Kalok·I. Tamir·S. Mitra·B. Sacepe·D. Shahar
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Abstract

In superconductors the zero-resistance current-flow is protected from dissipation at finite temperatures (T) by virtue of the short-circuit condition maintained by the electrons that remain in the condensed state. The recently suggested finite-T insulator and the "superinsulating" phase are different because any residual mechanism of conduction will eventually become dominant as the finite-T insulator sets-in. If the residual conduction is small it may be possible to observe the transition to these intriguing states. We show that the conductivity of the high magnetic-field insulator terminating superconductivity in amorphous indium-oxide exhibits an abrupt drop, and seem to approach a zero conductance at T<0.04 K. We discuss our results in the light of theories that lead to a finite-T insulator.

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M. Ovadia, D. Kalok, I. Tamir, S. Mitra, B. Sacepe, D. Shahar. 2014-06-29. Evidence for a Finite Temperature Insulator. https://doi.org/10.1038/srep13503

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