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arXiv · 1210.1826

Flat Chern Band in a Two-Dimensional Organometallic Framework

Zheng Liu·Zheng-Fei Wang·Jia-Wei Mei·Yong-Shi Wu·Feng Liu
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Abstract

By combining exotic band dispersion with nontrivial band topology, an interesting type of band structure, namely the flat chern band (FCB), has recently been proposed to spawn high-temperature fractional quantum hall states. Despite the proposal of several theoretical lattice models, however, it remains a doubt whether such a "romance of flatland" could exist in a real material. Here, we present a first-principles design of a two-dimensional (2D) Indium-Phenylene Organometallic Framework (IPOF) that realizes a nearly FCB 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 in virtue of organic chemistry and nanotechnology.

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Zheng Liu, Zheng-Fei Wang, Jia-Wei Mei, Yong-Shi Wu, Feng Liu. 2012-12-19. Flat Chern Band in a Two-Dimensional Organometallic Framework. https://doi.org/10.1103/physrevlett.110.106804

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