Topological superconductivity can be engineered in semiconductors with strong spin-orbit interaction coupled to a superconductor. Experimental advances in this field have often been triggered by the development of new hybrid material systems. Among these, two-dimensional electron gases (2DEGs) are of particular interest due to their inherent design flexibility and scalability. Here we discuss results on a 2D platform based on a ternary 2DEG (InSbAs) coupled to in-situ grown Aluminum. The spin-orbit coupling in these 2DEGs can be tuned with the As concentration, reaching values up to 400 meV\unicodexC5, thus exceeding typical values measured in its binary constituents. In addition to a large Land\'e g-factor ∼ 55 (comparable to InSb), we show that the clean superconductor-semiconductor interface leads to a hard induced superconducting gap. Using this new platform we demonstrate the basic operation of phase-controllable Josephson junctions, superconducting islands and quasi-1D systems, prototypical device geometries used to study Majorana zero modes.
@article{arxiv.2105.10437,
title = {InSbAs two-dimensional electron gases as a platform for topological superconductivity},
author = {Christian M. Moehle and Chung Ting Ke and Qingzhen Wang and Candice Thomas and Di Xiao and Saurabh Karwal and Mario Lodari and Vincent van de Kerkhof and Ruben Termaat and Geoffrey C. Gardner and Giordano Scappucci and Michael J. Manfra and Srijit Goswami},
journal= {arXiv preprint arXiv:2105.10437},
year = {2021}
}