Monolayer Kagome Metals AV${}_3$Sb${}_5$

Abstract

Recently, layered kagome metals AV${}_3$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 AV${}_3$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 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 AV${}_3$Sb${}_5$ as a promising platform for designer quantum phases.

6 figures + Supplementary Information, published version

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Cited by in corpus (10)

• AV${}_3$Sb${}_5$ Kagome Superconductors: Progress and Future Directions
• Two-dimensional Kagome Materials: Theoretical Insights, Experimental Realizations, and Electronic Structures
• Chiral-Flux-Phase-Based Topological Superconductivity in Kagome Systems with Mixed Edge Chiralities
• Kagome materials $A$V${}_3$Sb${}_5$ ($A$=K,Rb,Cs): pairing symmetry and pressure-tuning studies
• High-Throughput Discovery of Kagome Materials in Transition Metal Oxide Monolayers
• Origin of competing charge density waves in kagome metal ScV${}_6$Sn${}_6$
• MPd5 kagome superconductors studied by density functional calculations
• Charge-density wave fluctuation driven composite order in the layered Kagome Metals
• Stacking-Dependent Van Hove Singularity Shifts in Three-Dimensional Charge Density Waves of Kagome Metals AV${}_3$Sb${}_5$ (A = K, Rb, Cs)
• Designing Topological High-Order Van Hove Singularities: Twisted Bilayer Kagomé