We investigate the effect of a vertical electric field on a Dirac semimetal thin film. We show that through the interplay between the quantum confinement effect and the field-induced coupling between sub-bands, the sub-band gap can be tuned and inverted, during which the system undergoes a topological phase transition between a trivial band insulator and a quantum spin Hall insulator. Consequently, one can electrically switch the topological edge channels on and off, making the system a promising platform for constructing a topological field effect transistor.
@article{arxiv.1503.08075,
title = {Electric control of topological phase transitions in Dirac semimetal thin films},
author = {Hui Pan and Meimei Wu and Ying Liu and Shengyuan A. Yang},
journal= {arXiv preprint arXiv:1503.08075},
year = {2015}
}