腾讯会议ID：847-835-630

会议密码：1022

主持人：方辰 研究员

联系人：傅琦 (fuqi@iphy.ac.cn)

Abstract：The classification of quantum phases beyond symmetry breaking has transformed our understanding of ground states. How can this perspective be extended to thermal equilibrium states? In this talk, I will address this question using the three-dimensional toric code in transverse and longitudinal magnetic fields, which explicitly break both microscopic higher-form symmetries. I will introduce the connected correlation between two winding Wilson loops after local decoding of flux fluctuations. A nonzero value in the thermodynamic limit rules out preparation from product states by local channels whose causal range grows sublinearly with system size. I will also present quantum Monte Carlo results probing the decoded correlation across temperature and magnetic-field strengths.

Brief CV of Prof. Haruki Watanabe：
Haruki Watanabe is a Professor of Physics and an IAS Professor at the Hong Kong University of Science and Technology. He received his Ph.D. in Physics from the University of California, Berkeley, in 2015. After a Pappalardo Postdoctoral Fellowship at MIT, he joined the Department of Applied Physics at the University of Tokyo in 2016, where he served as Lecturer and later Associate Professor, before moving to HKUST in 2026. His research focuses on symmetry and topology in quantum many-body systems, including spontaneous symmetry breaking, topological phases, and frustration-free systems.