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arXiv · 1810.02591

Spin-orbit splitting of Andreev states revealed by microwave spectroscopy

L. Tosi·C. Metzger·M. F. Goffman·C. Urbina·H. Pothier·Sunghun Park·A. Levy Yeyati·J. Nygård·P. Krogstrup
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Abstract

We have performed microwave spectroscopy of Andreev states in superconducting weak links tailored in an InAs-Al (core-full shell) epitaxially-grown nanowire. The spectra present distinctive features, with bundles of four lines crossing when the superconducting phase difference across the weak link is 0 or $\pi.$ We interpret these as arising from zero-field spin-split Andreev states. A simple analytical model, which takes into account the Rashba spin-orbit interaction in a nanowire containing several transverse subbands, explains these features and their evolution with magnetic field. Our results show that the spin degree of freedom is addressable in Josephson junctions, and constitute a first step towards its manipulation.

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L. Tosi, C. Metzger, M. F. Goffman, C. Urbina, H. Pothier, Sunghun Park, A. Levy Yeyati, J. Nygård, P. Krogstrup. 2018-10-05. Spin-orbit splitting of Andreev states revealed by microwave spectroscopy. https://doi.org/10.1103/physrevx.9.011010

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