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arXiv · 1707.04154

Electric control of the bandgap in quantum wells with band-inverted junctions

A. Diaz-Fernandez·Leonor Chico·F. Dominguez-Adame
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Abstract

In IV-VI semiconductor heterojunctions with band-inversion, such as those made of Pb$_{1-x}$Sn$_{x}$Te or Pb$_{1-x}$Sn$_{x}$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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A. Diaz-Fernandez, Leonor Chico, F. Dominguez-Adame. 2017-11-15. Electric control of the bandgap in quantum wells with band-inverted junctions. https://doi.org/10.1088/1361-648x%2Faa91a6

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