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arXiv · 1907.00012

Stable Flatbands, Topology, and Superconductivity of Magic Honeycomb Networks

Jongjun M. Lee·Chenhua Geng·Jae Whan Park·Masaki Oshikawa·Sung-Sik Lee·Han Woong Yeom·Gil Young Cho
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Abstract

We propose a new principle to realize flatbands which are robust in real materials, based on a network superstructure of one-dimensional segments. This mechanism is naturally realized in the nearly commensurate charge-density wave of 1T-TaS${}_2$ with the honeycomb network of conducting domain walls, and the resulting flatband can naturally explain the enhanced superconductivity. We also show that corner states, which are a hallmark of the higher-order topological insulators, appear in the network superstructure.

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Jongjun M. Lee, Chenhua Geng, Jae Whan Park, Masaki Oshikawa, Sung-Sik Lee, Han Woong Yeom, Gil Young Cho. 2020-03-27. Stable Flatbands, Topology, and Superconductivity of Magic Honeycomb Networks. https://doi.org/10.1103/physrevlett.124.137002

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