Graphene, made of sp2 hybridized carbon, is characterized with a Dirac band, representative of its underlying 2D hexagonal lattice. Fundamental understanding of graphene has recently spurred a surge of searching for 2D topological quantum phases in solid-state materials. Here, we propose a new form of 2D material, consisting of sd2 hybridized transition metal atoms in hexagonal lattice, called sd2 graphene. The sd2 graphene is characterized with bond-centered electronic hopping, which transforms the apparent atomic hexagonal lattice into the physics of kagome lattice that may exhibit a wide range of topological quantum phases. Based on first-principles calculations, room temperature quantum anomalous Hall states with an energy gap of 0.1 eV are demonstrated for one such lattice made of W, which can be epitaxially grown on a semiconductor surface of 1/3 monolayer Cl-covered Si(111), with high thermodynamic and kinetic stability.
@article{arxiv.1411.0786,
title = {sd2 Graphene: Kagome Band in Hexagonal lattice},
author = {Miao Zhou and Zheng Liu and Wenmei Ming and Zhengfei Wang and Feng Liu},
journal= {arXiv preprint arXiv:1411.0786},
year = {2015}
}
Comments
Phys. Rev. Lett.(2014), In press. It includes main text and 5 figures. Supplemental material is available upon request