报告人|杨志成 研究员 北京大学

Zhi-Cheng Yang is an assistant professor at School of Physics, PekingUniversity. He received B.S. in physies from Peking University in 2013, andPh.D.in physics from Boston University in 2019, supervised by ClaudioChamon. He then moved to University of Maryland College Park as aPostdoctoral Researcher, before joining the current position in 2022.

时 间| 2025.12.2周二15:30-17:30

地点|物理楼 402

摘要|Mid-circuit measurements and feedback operations conditioned on theiroutcomes are essential primitives for realizing quantum error correction onmodern quantum hardware.Whenincorporated into quantum many-bodydynamics, these non-unitary operations can drive novel non-equilibrium phasetransitions both in the dynamics of individual quantum trajectories and in theensemble-averaged quantum channel. The wel-known measurement-inducedentanglement transition belongs to the former category. In this talk, I willintroduce a class of adaptive random-circuit models with feedback that exhibitphase transitions in both settings. By mapping the feedback-driven dynamics toclassical stochastic processes,we show that the resulting absorbing-statetransition falls into either the parity-conserving or directed-percolationuniversality class, depending on the feedback protocol. In the second part, I willpresent experimental results from a superconducting quantum processor featuringnigh-fidelity mid-circuit measurements and low-latency conditional feedbackwhere we directly observe the coexistence of measurement-induced entanglementand absorbing-state transitions.