iTHEMS Theoretical Physics Seminar by Wu Xianxin on June 5, 2025

On June 5, Prof. Xianxin Wu (the Institute of theoretical Physics, Chinese Academy of Sciences) delivered a seminar hosted by RIKEN iTHEMS, where he presented an overview of recent experimental advances in kagome metals. His talk highlighted key phenomena such as unconventional superconductivity, charge density wave (CDW) order, and electronic nematicity. Particularly noteworthy was the growing body of evidence indicating spontaneous time-reversal symmetry (TRS) breaking within the CDW phase—potentially signaling the emergence of a long-sought loop current order, although its microscopic origin remains unresolved. Following this overview, he discussed an effective theoretical model that captures the unique sublattice texture associated with van Hove singularities in the kagome lattice. This sublattice structure plays a crucial role in shaping correlated electronic states. To conclude the seminar, Xianxin proposed a theoretical scenario for the emergence of a TRS-breaking CDW in kagome systems and explored the possibility of unconventional superconducting pairing mediated by loop-current fluctuations.

Reported by Ching-Kai Chiu and Congcong Le