Simulated quantum annealing as a simulator of nonequilibrium quantum dynamics

Simulated quantum annealing based on the path-integral Monte Carlo is one of most common tools to simulate classical hardware. Nevertheless, it in principle highly non-trivial whether or not this algorithm can correctly reproduce dynamics annealing, particularly diabatic regime. We study problem numerically through generalized Kibble-Zurek mechanism defect distribution simplest ferromagnetic one-dimensional transverse-field Ising model with and without coupling environment. find that,in absence environment, simulated describes annealing-time dependence average number defects, but a detailed analysis shows clear deviations from theoretical prediction. When system open (coupled environment), defects does follow prediction qualitatively compatible numerical result by infinite time-evolving block decimation combined quasi-adiabatic propagator path integral, which valid very short time region. The turns out be far It surprising that stochastic ostensibly some aspects dynamics. However, serious hard predict for physical quantities reliable. Those results suggest necessity exert good amount caution using quantitative annealing.