KITS-IOP-ITP Joint Seminar
Title: Entanglement Steering in Adaptive Circuits with Feedback
Speaker: Prof. Zhi-cheng Yang (Peking University)
Time: Apr. 7 (Friday), 10:00
Place: Rm M830, IOP-CAS
Abstract: 
The dynamics of quantum entanglement in many-body systems is a subject of fundamental interest. Apart from completely unitary time evolutions, the competition between locally scrambling unitaries and local measurements can give rise to a novel non-equilibrium phenomena known as a measurement-induced phase transition. Usually, such a transition only shows up at the level of each individual quantum trajectory, and is absent for the density matrix averaged over measurement outcomes. In this work, we introduce a class of adaptive random circuit models with feedback that exhibit transitions in both settings. Interestingly, the transition for the density matrix and the entanglement transition in general happen at different critical measurement rates. We demonstrate that the former transition belongs to the parity-conserving universality class by explicitly mapping to a classical branching-annihilation random walk process.