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arXiv · 1403.1021

Quantum thermal Hall effect of Majorana fermions on the surface of superconducting topoloigcal insulators

Yosuke Shimizu·Ai Yamakage·Kentaro Nomura
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Abstract

We study the quantum anomalous thermal Hall effect in a topological superconductor which possesses an integer bulk topological number, and supports Majorana excitations on the surface. To realize the quantum thermal Hall effect, a finite gap at the surface is induced by applying an external magnetic field or by the proximity effects with magnetic materials or $s$-wave superconductors with complex pair-potentials. Basing on the lattice model Hamiltonian for superconducting states in Cu-doped Bi$_2$Se$_3$, we compute the thermal Hall conductivity as a function of various parameters such as the chemical potential, the pair-potential, and the spin-orbit coupling induced band gap. It is argued that the bulk topological invariant corresponds to the quantization rule of the thermal Hall conductivity induced by complex $s$-wave pair-potentials.

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Yosuke Shimizu, Ai Yamakage, Kentaro Nomura. 2015-05-01. Quantum thermal Hall effect of Majorana fermions on the surface of superconducting topoloigcal insulators. https://doi.org/10.1103/physrevb.91.195139

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