Reeg Christopher, Loss Daniel, Klinovaja Jelena
Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
Beilstein J Nanotechnol. 2018 Apr 23;9:1263-1271. doi: 10.3762/bjnano.9.118. eCollection 2018.
There have recently been several experiments studying induced superconductivity in semiconducting two-dimensional electron gases that are strongly coupled to thin superconducting layers, as well as probing possible topological phases supporting Majorana bound states in such setups. We show that a large band shift is induced in the semiconductor by the superconductor in this geometry, thus making it challenging to realize a topological phase. Additionally, we show that while increasing the thickness of the superconducting layer reduces the magnitude of the band shift, it also leads to a more significant renormalization of the semiconducting material parameters and does not reduce the challenge of tuning into a topological phase.
最近有几项实验研究了与薄超导层强耦合的半导体二维电子气中的诱导超导性，以及探索在此类设置中支持马约拉纳束缚态的可能拓扑相。我们表明，在这种几何结构中，超导体会在半导体中引起大的能带移动，从而使得实现拓扑相具有挑战性。此外，我们还表明，虽然增加超导层的厚度会减小能带移动的幅度，但这也会导致半导体材料参数发生更显著的重整化，并且不会降低调谐到拓扑相的难度。
