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arXiv · 1102.1322

Topology of Andreev Bound States with Flat Dispersion

Masatoshi Sato·Yukio Tanaka·Keiji Yada·Takehito Yokoyama
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Abstract

A theory of dispersionless Andreev bound states on surfaces of time-reversal invariant unconventional superconductors is presented. The generalized criterion for the dispersionless Andreev bound state is derived from the bulk-edge correspondence, and the chiral spin structure of the dispersionless Andreev bound states is argued from which the Andreev bound state is stabilized. Then we summarize the criterion in a form of index theorems. The index theorems are proved in a general framework to certify the bulk-edge correspondence. As concrete examples, we discuss (i) dxy-wave superconductor (ii) px-wave superconductor, and (iii) noncentrosymmetric superconductors. In the last example, we find a peculiar time-reversal invariant Majorana fermion. The time-reversal invariant Majorana fermion shows an unusual response to the Zeeman magnetic field, which can be used to identify it experimentally.

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Masatoshi Sato, Yukio Tanaka, Keiji Yada, Takehito Yokoyama. 2011-02-08. Topology of Andreev Bound States with Flat Dispersion. https://doi.org/10.1103/physrevb.83.224511

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