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arXiv · 1711.04056

Impurity-induced states in superconducting heterostructures

Dong E. Liu·Enrico Rossi·Roman M. Lutchyn
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Abstract

Heterostructures allow the realization of electronic states that are difficult to obtain in isolated systems. Exemplary is the case of quasi-one-dimensional heterostructures formed by a superconductor and a semiconductor with spin-orbit coupling in which Majorana zero-energy modes can be realized. We study the effect of a single impurity on the spectrum of superconducting heterostructures. We find that the coupling between the superconductor and the semiconductor can strongly affect the impurity-induced states and may induce additional subgap bound states that are not present in isolated uniform superconductors. For the case of quasi-one-dimensional superconductor/semiconductor heterostructures, we obtain the conditions for which the low-energy impurity-induced bound states appear.

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Dong E. Liu, Enrico Rossi, Roman M. Lutchyn. 2017-11-29. Impurity-induced states in superconducting heterostructures. https://doi.org/10.1103/physrevb.97.161408

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