Josephson current in ballistic Nb/InAs/Nb highly transmissive junctions
  Highly transmissive ballistic junctions are demonstrated between Nb and the two-dimensional electron gas formed at an InAs/AlSb heterojunction. A reproducible fabrication protocol is presented yielding high critical supercurrent values. Current-voltage characteristics were measured down to 0.4 K and the observed supercurrent behavior was analyzed within a ballistic model in the clean limit. This investigation allows us to demonstrate an intrinsic interface transmissivity approaching 90%. The reproducibility of the fabrication protocol makes it of interest for the experimental study of InAs-based superconductor-semiconductor hybrid devices. 
Francesco Giazotto (1), Kasper Grove-Rasmussen (1), Rosario Fazio (1),   Fabio Beltram (1), Edmund H. Linfield (2), and Davi...