Hybrid Quantum Point Contact-Superconductor Devices Using InSb Nanowires

Recent experiments using hybrid nanowire (NW)-superconductor (SC) devices have provided evidence for Majorana quasiparticles in tunneling experiments [1,2]. However, these tunneling experiments are marked by a soft superconducting gap, which likely originates from disorder at the NW-SC interface [3]. Hence, clean NW-SC interfaces are important for future Majorana studies. By carefully processing the NW-SC interface, we have realized quantized conductance steps in quantum point contacts fabricated from InSb NWs and superconducting contacts. We study the length dependence of ballistic behavior and the induced superconductivity in InSb NWs by quantum point contact spectroscopy. Additionally, we discuss how the transport in InSb NW-SC quantum point contacts evolves in magnetic field. \newline \newline References: 1. V. Mourik et al, Science 336, 1003 (2012). 2. A. Das et al, Nature Phys. 8, 887 (2012). 3. S. Takei et al, Phys. Rev. Lett. 110, 186803 (2013).