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Updated: Jun 8, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Surface band-gap narrowing in quantized electron accumulation layers
P D C King1, T D Veal, C F McConville
1Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom. philip.d.c.king@physics.org
Abstract:
An energy gap between the valence and the conduction band is the defining property of a semiconductor, and the gap size plays a crucial role in the design of semiconductor devices. We show that the presence of a two-dimensional electron gas near to the surface of a semiconductor can significantly alter the size of its band gap through many-body effects caused by its high electron density, resulting in a surface band gap that is much smaller than that in the bulk. Apart from reconciling a number of disparate previous experimental findings, the results suggest an entirely new route to spatially inhomogeneous band-gap engineering.
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