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.
@article{arxiv.1710.04300,
title = {Effective g-factor in Majorana Wires},
author = {S. Vaitiekėnas and M. T. Deng and J. Nygård and P. Krogstrup and C. M. Marcus},
journal= {arXiv preprint arXiv:1710.04300},
year = {2018}
}