2026/07/10 by Zhuo-Xuan Yang, Yi-Xiang Wang, Jiangfan Wang
#Topological Materials and Phenomena #Advanced Condensed Matter Physics #Quantum many-body systems
paper · pdf · doi:10.1016/j.physb.2026.419090
The interplay between band topology and strong correlations is central to modern condensed matter physics, but exact solutions are rare. Here, we present an exactly solvable model on the Kagome lattice by combining a Kane-Mele-type spin-orbit coupling with the Hatsugai-Kohmoto interaction. At 1/3 filling, we uncover a continuous topological quantum phase transition driven by electron interaction. A weakly correlated ℤ2 topological insulator gives way to a strongly correlated insulator that, while ℤ2-trivial, hosts a nontrivial spin Chern number Cs=2. The transition exhibits critical scaling consistent with the universality class of two-dimensional Dirac fermions. At half-filling, the same model yields a non-Fermi-liquid to Mott-insulator transition, demonstrating that correlation-driven topological and Mott transitions can be unified within a single solvable framework. Our results establish the Kagome Hatsugai-Kohmoto model as a valuable benchmark for interacting topological systems.