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arXiv · 1205.1441

Thermal metal-insulator transition in a helical topological superconductor

I. C. Fulga·A. R. Akhmerov·J. Tworzydło·B. Béri·C. W. J. Beenakker
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Abstract

Two-dimensional superconductors with time-reversal symmetry have a Z_2 topological invariant, that distinguishes phases with and without helical Majorana edge states. We study the topological phase transition in a class-DIII network model, and show that it is associated with a metal-insulator transition for the thermal conductance of the helical superconductor. The localization length diverges at the transition with critical exponent nu approx 2.0, about twice the known value in a chiral superconductor.

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I. C. Fulga, A. R. Akhmerov, J. Tworzydło, B. Béri, C. W. J. Beenakker. 2012-05-07. Thermal metal-insulator transition in a helical topological superconductor. https://doi.org/10.1103/physrevb.86.054505

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