Two-dimensional MX Dirac materials and quantum spin Hall insulators with tunable electronic and topological properties

We propose a novel class of two-dimensional (2D) Dirac materials in the MX family (M = Be, Mg, Zn and Cd, X = Cl, Br and I), which exhibit graphene-like band structures with linearly-dispersing Dirac-cone states over large energy scales (0.8–1.8 eV) and ultra-high Fermi velocities comparable to grap...

Full description

Saved in:
Bibliographic Details
Published in:Nano research 2021-03, Vol.14 (3), p.584-589
Main Authors: Zhang, Yan-Fang, Pan, Jinbo, Banjade, Huta, Yu, Jie, Lin, Hsin, Bansil, Arun, Du, Shixuan, Yan, Qimin
Format: Article
Language:English
Subjects:
Atomic/Molecular Structure and Spectra
Biomedicine
Biotechnology
Cadmium
Chemistry and Materials Science
Condensed Matter Physics
Coupling (molecular)
Density of states
Electric fields
Electron spin
Energy gap
Graphene
Insulators
Magnesium
Materials Science
Nanotechnology
Research Article
Spin-orbit interactions
Spintronics
Superconductivity
Topology
Zinc
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We propose a novel class of two-dimensional (2D) Dirac materials in the MX family (M = Be, Mg, Zn and Cd, X = Cl, Br and I), which exhibit graphene-like band structures with linearly-dispersing Dirac-cone states over large energy scales (0.8–1.8 eV) and ultra-high Fermi velocities comparable to graphene. Spin-orbit coupling opens sizable topological band gaps so that these compounds can be effectively classified as quantum spin Hall insulators. The electronic and topological properties are found to be highly tunable and amenable to modulation via anion-layer substitution and vertical electric field. Electronic structures of several members of the family are shown to host a Van-Hove singularity (VHS) close to the energy of the Dirac node. The enhanced density-of-states associated with these VHSs could provide a mechanism for inducing topological superconductivity. The presence of sizable band gaps, ultra-high carrier mobilities, and small effective masses makes the MX family promising for electronics and spintronics applications.
ISSN:1998-0124
1998-0000
DOI:10.1007/s12274-020-3022-3