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arXiv · 1807.03943

Distribution of Conductances in Chiral Topological Superconductor Junctions

Biao Lian·Jing Wang
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Abstract

We study the electronic transport of heterojunctions made of chiral topological superconductors (TSCs) with $N$ chiral Majorana fermion modes and quantum Hall insulators (QHIs) with integer Chern number $C$. In the weak disorder regime, we show the two-terminal conductance $σ_{12}$ of a QHI-TSC-QHI junction is generically non-quantized, but obeys a certain distribution determined by $C$ and $N$, which is induced by random SO($N$) rotations of chiral Majorana fermion mode basis on the TSC edges. Oppositely, in the strong disorder regime, $σ_{12}$ tends to be a quantized value. We conclude with a brief discussion on the fractionally quantized thermal conductances of the junction.

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Biao Lian, Jing Wang. 2018-07-11. Distribution of Conductances in Chiral Topological Superconductor Junctions. https://doi.org/10.1103/physrevb.99.041404

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