Universal scaling in Loschmidt echo across quantum phase transitions under nonadiabatic dynamics
Phys. Rev. B 112, 024310 – Published 18 July, 2025
DOI: https://doi.org/10.1103/lq1s-wx4d
Abstract
Universality and scaling are fundamental concepts in both equilibrium and dynamical phase transitions. Here, we unveil a universal scaling behavior of the critical time of the Loschmidt echo when the system is nonadiabatically driven across the quantum phase transitions. We find that the critical time exhibits a power-law scaling with quenching rate and the scaling exponent is fully determined by the underlining universality class of the equilibrium phase transitions. We explain this unique scaling behavior based on the adiabatic-impulse approximation in the Kibble-Zurek mechanism. This universal scaling behavior is verified to be valid not only in noninteracting single-particle system, but also in many-body interacting system, and not only in the Hermitian system, but also in the non-Hermitian system. Our study unravels a deep and fundamental relationship between dynamical behaviors and equilibrium phase transitions.
