In a closed system, thermalization occurs through unitary evolution, which encodes information in increasingly nonlocal degrees of freedom. Recent work on random quantum circuits has clarified how this non-local encoding is affected by an external observer: at a critical measurement rate the system undergoes a phase transition from an encoding state with volume law entanglement to an area law state. I will review the current understanding of the transition using a mapping to statistical mechanics models and use this description to predict two new phenomena. First, I will argue that large scale entanglement, with sub-volume critical power law scaling, is left in the monitored system when it is coupled to a decoherence channel at its edge. Second, I will show that the capacity of certain quantum circuits to facilitate quantum teleportation over infinite distances has a critical onset at a finite time.

Chair: Yuki Motome

This event is jointly organized by the Korea Institute for Advanced Study and the University of Tokyo. “Correlated Electrons Virtual International Seminars (CEVIS)”　https://sites.google.com/view/cevis2020/home