Quantum Error Correction in Scrambling Dynamics and Measurement-Induced Phase Transition

Understand

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.