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arXiv · 1804.08337

Proximity effect in a two-dimensional electron gas coupled to a thin superconducting layer

Christopher Reeg·Daniel Loss·Jelena Klinovaja
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Abstract

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.

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Christopher Reeg, Daniel Loss, Jelena Klinovaja. 2018-04-23. Proximity effect in a two-dimensional electron gas coupled to a thin superconducting layer. https://doi.org/10.3762/bjnano.9.118

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