RT Journal Article
T1 Robust midgap states in band-inverted junctions under electric and magnetic fields
A1 Díaz Fernández, Álvaro
A1 del Valle, Natalia
A1 Domínguez-Adame Acosta, Francisco
AB Several IV-VI semiconductor compounds made of heavy atoms, such as Pb1-xSnxTc, may undergo band-inversion at the L point of the Brillouin zone upon variation of their chemical composition. This inversion gives rise to topologically distinct phases, characterized by a change in a topological invariant. In the framework of the k.p theory, band-inversion can be viewed as a change of sign of the fundamental gap. A two-band model within the envelope-function approximation predicts the appearance of midgap interface states with Dirac cone dispersions in band-inverted junctions, namely, when the gap changes sign along the growth direction. We present a thorough study of these interface electron states in the presence of crossed electric and magnetic fields, the electric field being applied along the growth direction of a band-inverted junction. We show that the Dirac cone is robust and persists even if the fields are strong. In addition, we point out that Landau levels of electron states lying in the semiconductor bands can be tailored by the electric field. Tunable devices are thus likely to be realizable, exploiting the properties studied herein.
PB Beilstein-Institut
SN 2190-4286
YR 2018
FD 2018-03-14
LK https://hdl.handle.net/20.500.14352/12185
UL https://hdl.handle.net/20.500.14352/12185
LA eng
NO © Beilstein-Institut.The authors thank L. Chico and J. W. González for helpful discussions. This work was supported by the Spanish MINECO under grant MAT2016-75955.
NO Ministerio de Economía y Competitividad (MINECO)
DS Docta Complutense
RD 17 ago 2024