Monolayer Kagome metals AV3Sb5

• Published in: Nature communications Vol. 14; no. 1; pp. 591 - 10
• Main Authors: Kim, Sun-Woo, Oh, Hanbit, Moon, Eun-Gook, Kim, Youngkuk
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.02.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/119/1003; 639/301/119/2792/4128; 639/301/119/995; Cesium; Charge density waves; First principles; Heavy metals; Humanities and Social Sciences; Metals; Monolayers; multidisciplinary; Rubidium; Science; Science (multidisciplinary); Singularity (mathematics); Stoichiometry; Superconductivity; Topology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-36341-2

Recently, layered kagome metals A V 3 Sb 5 ( 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 A V 3 Sb 5 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 A V 3 Sb 5 as a promising platform for designer quantum phases. Much recent work has focused on the kagome metals AV 3 Sb 5 (A = K, Rb, and Cs), but studies of the monolayer form are only just beginning. Here, the authors theoretically study monolayer kagome metals, and predict modified van Hove singularities that lead to charge-density-wave doublets and d-wave superconductivity.