Universal KPZ scaling in noisy hybrid quantum circuits

演讲人: 刘铄 清华大学
时间: 2023-02-15 19:15-2023-02-15 20:15
地点:Tencent Meeting: 999 663 621 (ps:1984)+MMW S327
内容:

Measurement-induced phase transitions (MIPT) have attracted increasing attention due to the rich phenomenology of entanglement structures and their relation with quantum information processing. Since physical systems are unavoidably coupled to the environment, quantum noise, which can qualitatively modify or even destroy certain entanglement structures, needs to be considered in analyzing a system with MIPT. We investigate the effect of quantum noise modeled by a reset quantum channel acting on each site with a probability q on MIPT. Based on the numerical results from Clifford circuits, we show that the quantum noise can qualitatively change the entanglement properties - the entanglement obeys “area law” instead of “volume law” with a measurement rate p < pc. In the quantum noise-induced “area law” phase, the entanglement exhibits a novel q−1/3 power-law scaling. Using an analytic mapping from the quantum model to a classical statistical model, we further show that the “area law” entanglement is the consequence of the noise-driven symmetry-breaking field and the q−1/3 scaling can be understood as the result of Kardar-Parisi-Zhang (KPZ) fluctuations of the directed polymer with an effective length scale Leff ∼ q−1 in a random environment.

个人简介:

刘铄是清华大学高等研究院三年级博士生,导师为姚宏教授。刘铄2020年毕业于北京师范大学物理学系,获得学士学位。研究方向包括量子多体系统和非平衡物理中的新奇现象。