Speaker: Paolo Muratore-Ginanneschi
Title: Quantum master equations are unraveled by Markov processes.
We show that general time-local quantum master equations admit an unravelling in quantum trajectories with jumps. The sufficient condition is to weigh state vector Monte Carlo averages by a probability pseudo-measure which we call the "influence martingale". The influence martingale satisfies a 1d stochastic differential equation enslaved to the ones governing the quantum trajectories. Our interpretation is that the influence martingale models interference effects between distinct realizations of the quantum trajectories at strong system-environment coupling. If the master equation generates a completely positive dynamical map, there is no interference. In such a case the influence martingale becomes positive definite and the Monte Carlo average straightforwardly reduces to the well known unravelling of completely positive divisible dynamical maps.
The talk is based on arXiv:2102.10355 in collaboration with Brecht Donvil.