Quantum meeting: Geometric phases along quantum trajectories: ensembles and topological transitions

MdM Quantum Meeting

In this presentation, we explore the dynamics of a continuously and indirectly monitored open quantum system subject to cyclic driving, where the geometric phase accumulated is intricately dependent by both the unitary dynamics and the interaction with the monitored environment. Consequently, the geometric phase shows a stochastic character inherited from the randomness in the occurrence of quantum jumps. Focusing on the illustrative scenario of a spin-1/2 in a time-varying magnetic field within an external environment, we investigate the distribution function of geometric phases. This exploration enables discussion on representativeness of various quantities in relation to this distribution, and sheds light on the circumstances under which an echo protocol may successfully measure the geometric phase. Additionally,  through the study of the phase acquired in a driving cycle, we unveil a topological transition on the no-jumps dynamics.

https://us06web.zoom.us/j/83133308308?pwd=5cn6lGRCeypwzi8TA6eO6ODaeBHRqq.1