Decoherent Quench Across Quantum Phase Transitions

Monitored quantum dynamics has attracted much research attention recently. Environmental monitoring typically leads to the decoherence of a quantum system. We explore the effect of energy-level decoherence in quench dynamics. In particular, we consider the linear quench across quantum critical phase transitions under the influence of decoherence. Due to the critical slowing down, the system will necessarily fall out of equilibrium in the vicinity of the critical point within a time scale known as the freeze-out time. The freeze-out time will scale with the quench rate following the Kibble-Zurek scaling. In the presence of decoherence, we found a new scaling behavior differed from the Kibble-Zurek scaling. We demonstrated our findings in the critical quench between 2D Chern insulator and trivial insulator. We show that the new scaling behavior can be justified from the behavior of Hall conductivity across the quantum quench.