Intertwined van-Hove Singularities as a Mechanism for Loop Current Order in Kagome Metals

Abstract

Recent experiments on Kagome metals AV${}_3$Sb${}_5$ (A=Cs,Rb,K) indicated spontaneous time-reversal symmetry breaking in the charge density wave state in the absence of static magnetization. The loop current order (LCO) is proposed as its cause, but a microscopic model explaining the emergence of LCO through electronic correlations has not been firmly established. We show that the coupling between van-Hove singularities (vHS) with distinct mirror symmetries is a key ingredient to generate LCO ground state. By constructing an effective model, we find that when multiple vHS with opposite mirror eigenvalues are close in energy, the nearest-neighbor electron repulsion favors a ground state with coexisting LCO and charge bond order. It is then demonstrated that this mechanism applies to the Kagome metals AV${}_3$Sb${}_5$. Our findings provide an intriguing mechanism of LCO and pave the way for a deeper understanding of complex quantum phenomena in Kagome systems.

References in corpus (10)

• CsV${}_3$Sb${}_5$: a ${\mathbb{Z}}_2$ topological kagome metal with a superconducting ground state
• Superconductivity in the ${\mathbb{Z}}_2$ kagome metal KV${}_3$Sb${}_5$
• Unusual competition of superconductivity and charge-density-wave state in a compressed topological kagome metal
• Absence of local moments in the kagome metal KV3Sb5 as determined by muon spin spectroscopy
• Loop currents in $A$V${}_3$Sb${}_5$ kagome metals: multipolar and toroidal magnetic orders
• Temperature-driven reorganization of electronic order in CsV${}_3$Sb${}_5$
• Charge density wave order in kagome metal AV${}_3$Sb${}_5$ (A= Cs, Rb, K)
• Superconductivity from repulsive interactions on the kagome lattice
• Theory of nematic charge orders in kagome metals
• Tri-Hexagonal charge order in kagome metal CsV${}_3$Sb${}_5$ revealed by ${}^{121}$Sb NQR

Cited by in corpus (18)

• Correlated Electronic Structure and Incipient Flat Bands of the Kagome Superconductor CsCr3Sb5
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• Exotic charge density waves and superconductivity on the Kagome Lattice
• Electronic structure of $A$V${}_3$Sb${}_5$ kagome metals
• Loop Current Order on the Kagome Lattice
• Interplay of Charge Density Wave and Magnetism on the Kagomé Lattice
• Unveiling the nature of electronic transitions in RbV${}_3$Sb${}_5$ with Avoided Level Crossing $\mu$SR
• Loop-current order through the kagome looking glass
• Multiple topological corner states in the continuum of extended kagome lattice
• Inter-Layer Correlation of Loop Current Charge Density Wave on the Bilayer Kagomé Lattice
• Beyond kagome: $p$-bands in kagome metals
• Orbital altermagnetism on the kagome lattice and possible application to $A$V${}_3$Sb${}_5$
• Kekulé order from diffuse nesting near higher-order Van Hove points
• Anisotropic scattering rates in strain-tuned Sr${}_2$RuO${}_4$
• Theory of unconventional magnetism in a Cu-based kagome metal
• Electronic and structural properties of Rh- and Pd-based kagome layered shandites from first principles
• Topological pair density waves in kagome superconductors