Professional Education


  • Doctor of Philosophy, University of California Berkeley (2023)
  • BSc, Peking University, Physics (2017)

Stanford Advisors


Current Research and Scholarly Interests


I am a theoretical physicist working at the intersection of condensed matter physics and quantum information science. My research explores the many-body aspects of quantum information and novel collective phenomena both in and out of equilibrium using various analytical and numerical methods. A few specific recent interests include quantum error correction, mixed-state topological phases, and numerical and analytical methods based on tensor network formulations.

All Publications


  • Quantum Error Correction in Scrambling Dynamics and Measurement-Induced Phase Transition. Physical review letters Choi, S., Bao, Y., Qi, X. L., Altman, E. 2020; 125 (3): 030505

    Abstract

    We analyze the dynamics of entanglement entropy in a generic quantum many-body open system from the perspective of quantum information and error corrections. We introduce a random unitary circuit model with intermittent projective measurements, in which the degree of information scrambling by the unitary and the rate of projective measurements are independently controlled. This model displays two stable phases, characterized by the volume-law and area-law scaling entanglement entropy in steady states. The transition between the two phases is understood from the point of view of quantum error correction: the chaotic unitary evolution protects quantum information from projective measurements that act as errors. A phase transition occurs when the rate of errors exceeds a threshold that depends on the degree of information scrambling. We confirm these results using numerical simulations and obtain the phase diagram of our model. Our work shows that information scrambling plays a crucial role in understanding the dynamics of entanglement in an open quantum system and relates the entanglement phase transition to changes in quantum channel capacity.

    View details for DOI 10.1103/PhysRevLett.125.030505

    View details for PubMedID 32745425