时间：3月14日(周四)上午9：30

地点：勤园20-518

报告摘要：

The study of phase transitions is always fascinating for physicists. In a phase transition, the main characteristics of a system change drastically under relatively small variations in the governing parameters, such as temperature and external fields. While equilibrium phase transitions have been extensively studied, the behavior of physical systems, particularly quantum systems out of equilibrium, is not as well understood. This is why the investigation of non-equilibrium dynamics in quantum many-body models has garnered significant attention. In this context, I will present our recent research on exploring dynamical phase transitions in quantum spin models. Firstly, we examine the nonanalytic behavior of the Loschmidt echo during the early-time evolution following a quench, which is known as a dynamical quantum phase transition. Secondly, we analyze the relaxation dynamics of the two-point fermion correlation function during the long-term evolution after the quench, identifying different scaling behaviors that define the dynamical phase. In summary, our research delves into the intricate dynamics of quantum spin models, shedding light on the fascinating realm of non-equilibrium phase transitions in quantum systems.

报告人简介：

曹凯源，助理研究员，2022年获南京师范大学理论物理专业博士学位，目前在之江实验室做博士后。研究兴趣包含量子相变、量子多体系统的动力学行为以及机器学习与统计物理交叉学科等方向。在Phys. Rev. B、J. Phys.: Condens. Matter等国内外著名物理期刊发表SCI论文7篇，担任Phys. Rev. B/Physica Scripta/J. Phys. Condens. Matt./Chin. Phys. B/物理学报等物理期刊审稿人。