Speaker
Description
Vanadium-based Kagome metals AV3Sb5(A = K, Rb, Cs) host competing charge density wave (CDW) states driven by enhanced correlations from van Hove singularities. These include Star-of-David and Tri-Hexagonal patterns, along with nematicity and possible time-reversal symmetry breaking, suggesting a loop-current order. These strongly competing phases make them promising for optical control, where photons can excite collective modes or manipulate ordered states.
However, the microscopic mechanism of the charge order—whether dominated by electron interactions or electron–phonon coupling--remains unclear. In this talk, we address this question using a Hartree–Fock mean-field approach based on an ab-initio model with electron–phonon couplings. We discuss how interaction form factors shape symmetry breaking across multiple free-energy minima, and study photoinduced dynamics with Ehrenfest dynamics. These results provide a microscopic basis for optical control of complex ordered states in Kagome metals.