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arXiv · 1403.6421

Bimodal conductance distribution of Kitaev edge modes in topological superconductors

M. Diez·I. C. Fulga·D. I. Pikulin·J. Tworzydlo·C. W. J. Beenakker
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Abstract

A two-dimensional superconductor with spin-triplet p-wave pairing supports chiral or helical Majorana edge modes with a quantized (length $L$-independent) thermal conductance. Sufficiently strong anisotropy removes both chirality and helicity, doubling the conductance in the clean system and imposing a super-Ohmic $1/\sqrt{L}$ decay in the presence of disorder. We explain the absence of localization in the framework of the Kitaev Hamiltonian, contrasting the edge modes of the two-dimensional system with the one-dimensional Kitaev chain. While the disordered Kitaev chain has a log-normal conductance distribution peaked at an exponentially small value, the Kitaev edge has a bimodal distribution with a second peak near the conductance quantum. Shot noise provides an alternative, purely electrical method of detection of these charge-neutral edge modes.

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M. Diez, I. C. Fulga, D. I. Pikulin, J. Tworzydlo, C. W. J. Beenakker. 2014-03-25. Bimodal conductance distribution of Kitaev edge modes in topological superconductors. https://doi.org/10.1088/1367-2630%2F16%2F6%2F063049

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