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arXiv · 1710.04300

Effective g-factor in Majorana Wires

S. Vaitiekėnas·M. T. Deng·J. Nygård·P. Krogstrup·C. M. Marcus
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Abstract

We use the effective g-factor of subgap states, g*, in hybrid InAs nanowires with an epitaxial Al shell to investigate how the superconducting density of states is distributed between the semiconductor core and the metallic shell. We find a step-like reduction of g* and improved hard gap with reduced carrier density in the nanowire, controlled by gate voltage. These observations are relevant for Majorana devices, which require tunable carrier density and g* exceeding the g-factor of the proximitizing superconductor. Additionally, we observe the closing and reopening of a gap in the subgap spectrum coincident with the appearance of a zero-bias conductance peak.

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S. Vaitiekėnas, M. T. Deng, J. Nygård, P. Krogstrup, C. M. Marcus. 2018-10-05. Effective g-factor in Majorana Wires. https://doi.org/10.1103/physrevlett.121.037703

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