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arXiv · 1204.3382

Theory of tunneling spectroscopy for chiral topological superconductors

Akihiro Ii·Ai Yamakage·Keiji Yada·Masatoshi Sato·Yukio Tanaka
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Abstract

We study the charge conductance of an interface between a normal metal and a superconducting quantum anomalous Hall system, based on the recursive Green's function. The angle resolved conductance gamma(ky, eV) with the momentum ky parallel to the interface and the bias voltage V shows a rich structure depending on the Chern number N of the system. We find that when the bias voltage is tuned to the energy dispersion of the edge mode, eV = Eedge(ky), the angle resolved conductance gamma(ky,Eedge(ky)) shows a pronounced even-odd effect; the conductance vanishes for N = 0 or 2 while it takes a universal value 2e^2/h for N = 1. In particular, in N = 2 phase, we find that the conductance gamma(ky,Eedge(ky)) becomes zero due to interference of two degenerate Majorana edge modes, although the corresponding surface spectral weight remains non-zero.

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Akihiro Ii, Ai Yamakage, Keiji Yada, Masatoshi Sato, Yukio Tanaka. 2012-10-06. Theory of tunneling spectroscopy for chiral topological superconductors. https://doi.org/10.1103/physrevb.86.174512

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