Bismuth nanowires with in situ shadow deposited Josephson junctions

Abstract

Single crystal bismuth nanowires have been recently identified as a high-order topological system, in which the crystal “hinges” host a one dimensional helical transport channel. To date, studies on the superconducting transport in these channels have relied on an aggressive surface treatment required to strip the oxidized nanowire surface prior to deposition of a superconductor in a process that will inevitably cause some damage to the surface. In this report, we describe the growth and characterization of bismuth nanowires with in situ deposited superconducting contacts, which avoid the requirement to treat the nanowire surface for oxide removal. The described shadow deposition method may avoid damage to the bismuth nanowire surface, supplying a higher-quality platform for exploring the topological quantum transport in bismuth nanowire based Josephson junctions.