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arXiv · 1511.03877

Phase-tunable Majorana bound states in a topological N-SNS junction

Esben Bork Hansen·Jeroen Danon·Karsten Flensberg
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Abstract

We theoretically study the differential conductance of a one-dimensional normal-superconductor-normal-superconductor (N-SNS) junction with a phase bias applied between the two superconductors. We consider specifically a junction formed by a spin-orbit coupled semiconducting nanowire with regions of the nanowire having superconducting pairing induced by a bulk $s$-wave superconductor. When the nanowire is tuned into a topologically non-trivial phase by a Zeeman field, it hosts zero-energy Majorana modes at its ends as well as at the interface between the two superconductors. The phase-dependent splitting of the Majorana modes gives rise to features in the differential conductance that offer a clear distinction between the topologically trivial and non-trivial phases. We calculate the transport properties of the junction numerically and also present a simple analytical model that captures the main properties of the predicted tunneling spectroscopy.

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Esben Bork Hansen, Jeroen Danon, Karsten Flensberg. 2016-02-24. Phase-tunable Majorana bound states in a topological N-SNS junction. https://doi.org/10.1103/physrevb.93.094501

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