Supercurrent interference in few-mode nanowire Josephson junctions
Abstract
Junctions created by coupling two superconductors via a semiconductor nanowire in the presence of high magnetic fields are the basis for detection, fusion, and braiding of Majorana bound states. We study NbTiN/InSb nanowire/NbTiN Josephson junctions and find that their critical currents in the few mode regime are strongly suppressed by magnetic field. Furthermore, the dependence of the critical current on magnetic field exhibits gate-tunable nodes. Based on a realistic numerical model we conclude that the Zeeman effect induced by the magnetic field and the spin-orbit interaction in the nanowire are insufficient to explain the observed evolution of the Josephson effect. We find the interference between the few occupied one-dimensional modes in the nanowire to be the dominant mechanism responsible for the critical current behavior. The suppression and non-monotonic evolution of critical currents at finite magnetic field should be taken into account when designing circuits based on Majorana bound states.
Cite
@article{arxiv.1706.03331,
title = {Supercurrent interference in few-mode nanowire Josephson junctions},
author = {Kun Zuo and Vincent Mourik and Daniel B. Szombati and Bas Nijholt and David J. van Woerkom and Attila Geresdi and Jun Chen and Viacheslav P. Ostroukh and Anton R. Akhmerov and Sebastién R. Plissard and Diana Car and Erik P. A. M. Bakkers and Dmitry I. Pikulin and Leo P. Kouwenhoven and Sergey M. Frolov},
journal= {arXiv preprint arXiv:1706.03331},
year = {2017}
}
Comments
Published version, ref 36 included here