Supercurrent in InSb Nanowires Quantum Point Contacts

Quantum point contacts is narrow constriction between two electrically conducting materials and emerges at contacting region. It indicates ballistic electron transport and allow us to study physics in the regime of single and several electrons occupied sub-bands.

We study superconductivity induced by NbTiN in InSb nanowires and find Quantized conductance at low and high field, which indicate QPC in the device. We observe supercurrents of the regime of a single occupied sub-band and study their magnetic field evolution. In the multimode regime where multiple one-dimensional sub-bands are occupied, supercurrent interference due to magnetic field has been reported. It is predicted that in the limit of a single occupied sub-band interference is suppressed and supercurrents can be observed to high magnetic fields, allowing the study of spin-orbit and Zeeman effects on the Josephson effect. 

10/2019