Topological Superconductivity and Surface Andreev Bound States in Doped Semiconductors: Application to CuxBi2Se3

TL;DR

This paper investigates the surface Andreev bound states and Majorana fermions in the topological superconductor CuxBi2Se3, combining analytical, numerical, and experimental insights to advance understanding of its surface states.

Contribution

It provides a detailed analytical and numerical analysis of surface Andreev bound states and Majorana fermions in CuxBi2Se3, linking theoretical predictions with experimental observations.

Findings

Identification of topologically protected Majorana fermions at k=0

Discovery of a new type of surface Andreev bound states at finite k

Correlation of theoretical results with point-contact spectroscopy data

Abstract

The recently discovered superconductor CuxBi2Se3[1] is a candidate for three-dimensional time-reversal-invariant topological superconductors[2], which are predicted to have robust surface Andreev bound states hosting massless Majorana fermions. In this work, we present an analytical and numerical study of the surface Andreev bound state wavefunction and dispersion. We find the topologically protected Majorana fermions at k = 0, as well as a new type of surface Andreev bound states at finite k. We relate our results to a recent point-contact spectroscopy experiment[3].