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arXiv · 1106.6265

Disorder-induced Majorana metal in interacting non-Abelian anyon systems

Chris R. Laumann·Andreas W. W. Ludwig·David A. Huse·Simon Trebst
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Abstract

We demonstrate that a thermal metal of Majorana fermions forms in a two-dimensional system of interacting non-Abelian (Ising) anyons in the presence of moderate disorder. This bulk metallic phase arises in the $\nu=5/2$ quantum Hall state when disorder pins the anyonic quasiparticles. More generally, it naturally occurs for various proposed systems supporting Majorana fermion zero modes when disorder induces the random pinning of a finite density of vortices. This includes all two-dimensional topological superconductors in so-called symmetry class D. A distinct experimental signature of the thermal metal phase is the presence of bulk heat transport down to zero temperature.

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Chris R. Laumann, Andreas W. W. Ludwig, David A. Huse, Simon Trebst. 2011-06-30. Disorder-induced Majorana metal in interacting non-Abelian anyon systems. https://doi.org/10.1103/physrevb.85.161301

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