title: Flat Chern band in a two-dimensional organometallic framework.
abstract: By combining exotic band dispersion with nontrivial band topology, an interesting type of band structure, namely, the flat Chern band, has recently been proposed to spawn high-temperature fractional quantum Hall states. Despite the proposal of several theoretical lattice models, however, it remains doubtful whether such a "romance of flatland" could exist in a real material. Here, we present a first-principles design of a two-dimensional indium-phenylene organometallic framework that realizes a nearly flat Chern band right around the Fermi level by combining lattice geometry, spin-orbit coupling, and ferromagnetism. An effective four-band model is constructed to reproduce the first-principles results. Our design, in addition, provides a general strategy to synthesize topologically nontrivial materials by virtue of organic chemistry and nanotechnology.
authors.affiliation: Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Zheng-Fei
authors.initials: ZF
authors.lastname: Wang
authors.forename: Jia-Wei
authors.initials: JW
authors.lastname: Mei
authors.forename: Yong-Shi
authors.initials: YS
authors.lastname: Wu
authors.forename: Feng
authors.initials: F
authors.lastname: Liu