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Monolayer Kagome metals AV₃Sb₅.

ABSTRACT: Recently, layered kagome metals AV₃Sb₅ (A = K, Rb, and Cs) have emerged as a fertile platform for exploring frustrated geometry, correlations, and topology. Here, using first-principles and mean-field calculations, we demonstrate that AV₃Sb₅ can crystallize in a mono-layered form, revealing a range of properties that render the system unique. Most importantly, the two-dimensional monolayer preserves intrinsically different symmetries from the three-dimensional layered bulk, enforced by stoichiometry. Consequently, the van Hove singularities, logarithmic divergences of the electronic density of states, are enriched, leading to a variety of competing instabilities such as doublets of charge density waves and s- and d-wave superconductivity. We show that the competition between orders can be fine-tuned in the monolayer via electron-filling of the van Hove singularities. Thus, our results suggest the monolayer kagome metal AV₃Sb₅ as a promising platform for designer quantum phases.

SUBMITTER: Kim SW

PROVIDER: S-EPMC9898313 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Monolayer Kagome metals AV3Sb5.

Kim Sun-Woo SW Oh Hanbit H Moon Eun-Gook EG Kim Youngkuk Y

Nature communications 20230203 1

Recently, layered kagome metals AV3Sb5 (A = K, Rb, and Cs) have emerged as a fertile platform for exploring frustrated geometry, correlations, and topology. Here, using first-principles and mean-field calculations, we demonstrate that AV3Sb5 can crystallize in a mono-layered form, revealing a range of properties that render the system unique. Most importantly, the two-dimensional monolayer preserves intrinsically different symmetries from the three-dim ...[more]

PMID: 36737613

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