title: sd(2) Graphene: Kagome band in a hexagonal lattice.
abstract: Graphene, made of sp^{2} hybridized carbon, is characterized with a Dirac band, representative of its underlying 2D hexagonal lattice. The fundamental understanding of graphene has recently spurred a surge in the search for 2D topological quantum phases in solid-state materials. Here, we propose a new form of 2D material, consisting of sd^{2} hybridized transition metal atoms in hexagonal lattice, called sd^{2} "graphene." The sd^{2} graphene is characterized by bond-centered electronic hopping, which transforms the apparent atomic hexagonal lattice into the physics of a 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.
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Utah 84112, USA.
authors.forename: Miao
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Utah 84112, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Utah 84112, USA.
authors.forename: Wenmei
authors.initials: W
authors.lastname: Ming
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Utah 84112, USA.
authors.forename: Zhengfei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Utah 84112, USA and Collaborative Innovation Center of Quantum Matter, Beijing 100084, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu