2020/08/31 by Marco Valentini, Fernando Peñaranda, Andrea Hofmann +8 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Andreev reflection #Bound state #Condensed matter physics #Electrical engineering #Graphene research and applications #Heterojunction #MAJORANA #Nanowire #Physics #Quantum mechanics #Quantum tunnelling #Quasiparticle #Semiconductor #Superconductivity #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1126/science.abf1513
published as Science 373, 82-88 (2021)
openalex publication_date 2021/07/01 · arxiv created 2021/08/10 · arxiv updated 2021/08/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
A semiconducting nanowire fully wrapped by a superconducting shell has been proposed as a platform for obtaining Majorana modes at small magnetic fields. In this study, we demonstrate that the appearance of subgap states in such structures is actually governed by the junction region in tunneling spectroscopy measurements and not the full-shell nanowire itself. Short tunneling regions never show subgap states, whereas longer junctions always do. This can be understood in terms of quantum dots forming in the junction and hosting Andreev levels in the Yu-Shiba-Rusinov regime. The intricate magnetic field dependence of the Andreev levels, through both the Zeeman and Little-Parks effects, may result in robust zero-bias peaks-features that could be easily misinterpreted as originating from Majorana zero modes but are unrelated to topological superconductivity.