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

Timothy H. Hsieh; Liang Fu

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arXiv · 1109.3464

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

Timothy H. Hsieh·Liang Fu

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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].

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Timothy H. Hsieh, Liang Fu. 2011-10-11. Topological Superconductivity and Surface Andreev Bound States in Doped Semiconductors: Application to CuxBi2Se3. https://arxiv.org/abs/1109.3464

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