Phase winding effects in hollow semiconductor nanowires with superconducting shells have been proposed as a route to engineer topological superconducting states. We investigate GaAs/InAs core/shell nanowires with half-shells of epitaxial aluminium as a potential platform for such devices, where the thin InAs shell confines the electron wave function around the GaAs core. With normal contacts we observed pronounced h/e flux periodic oscillations in the magnetoconductance, indicating the presence of a tubular conductive channel in the InAs shell. Conversely, the switching current in Josephson junctions oscillates with approximately half that period, i.e. h/2e, indicating transport via Andreev transport processes in the junction enclosing threading magnetic flux. On these structures, we systematically studied the gate-, field-, and temperature-dependent evolution of the supercurrent. Results indicate that Andreev transport processes can occur about the wire circumference indicating full proximitization of the InAs shell from the half-shell superconducting contacts.
@article{arxiv.2402.13880,
title = {Flux-periodic supercurrent oscillations in an Aharonov-Bohm-type nanowire Josephson junction},
author = {Patrick Zellekens and Russell S. Deacon and Farah Basaric and Raghavendra Juluri and Michael D. Randle and Benjamin Bennemann and Christoph Krause and Erik Zimmermann and Ana M. Sanchez and Detlev Grützmacher and Alexander Pawlis and Koji Ishibashi and Thomas Schäpers},
journal= {arXiv preprint arXiv:2402.13880},
year = {2024}
}