Topology of the Fermi surface and universality of the metal-metal and metal-insulator transitions: -dimensional Hatsugai-Kohmoto model as an example
This paper advances the theory of Fermi Surface Topology (FST) transitions by analyzing the exactly solvable -dimensional Hatsugai-Kohmoto model to demonstrate that the FST universality class, characterized by the Euler characteristic and Lee-Yang zeros, robustly describes metal-insulator and gapless-to-gapless transitions across various interaction regimes.