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Updated: Feb 21, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Electric control of the bandgap in quantum wells with band-inverted junctions
A Díaz-Fernández1,2, Leonor Chico3, F Domínguez-Adame1,2
1GISC, Departamento de Física de Materiales, Universidad Complutense, E-28040 Madrid, Spain.
Abstract:
In IV-VI semiconductor heterojunctions with band-inversion, such as those made of [Formula: see text] [Formula: see text]Te or [Formula: see text] [Formula: see text]Se, interface states are properly described by a two-band model, predicting the appearance of a Dirac cone in single junctions. However, in quantum wells the interface dispersion is quadratic in momentum and the energy spectrum presents a gap. We show that the interface gap shrinks under an electric field parallel to the growth direction. Therefore, the interface gap can be dynamically tuned in experiments on double-gated quantum wells based on band-inverted compounds.
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