时间：2025年4月21日（周一）下午14:00-15:30

Time: 14:00-15:30, Monday, April 21, 2025

地点： 西湖大学云谷校区E10-405

Venue: E10-405, Yungu Campus

主持人：西湖大学理学院讲席教授 吴从军

Host: Chair Professor Congjun Wu, School of Science, Westlake University

报告语言：英文

Language: English

吴建达博士，上海交通大学教授/李政道研究所研究员

Dr. Jianda Wu, Professor/ Researcher Fellow at the School of Physics and Astronomy 

Shanghai Jiao Tong University/Tsung-Dao Lee Institute

主讲人简介/Biography: 

Prof. Jianda Wu has long been committed to the research work in quantum phase transitions, quantum critical thermodynamics and dynamics, Bethe ansatz, and dynamics in quantum integrable systems. He obtained B.S. (2004) and M.S. (2007) degrees from University of Science and Technology of China, and got Ph.D. (2014) from Rice University. From 2014-2017 he carried out postdoc research at University of California at San Diego, then (2017-2018) became a guest scientist at Max Planck Institute for the Physics of Complex Systems. Since 2018 he became a Tsung-Dao Lee Fellow at Tsung-Dao Lee Institute and a faculty member at School of Physics and Astronomy at Shanghai Jiao Tong University. Jianda has published more than 30 papers including Nature, Nature Physics, Nature Communications, and Phys. Rev. Lett. etc. So far, he has delivered more than 80 invited talks at international conferences/workshops, and institutes around the world.

摘要/Abstract:

When two quantum critical transverse-field Ising chains (TFIC) are weakly coupled, the weak inter-chain coupling can drive the system to emerge as an integrable model with eight particles, organized by the Lie algebra. Realizing the quantum criticality of the TFIC is a key step to access the exotic integrable system. In my talk, after briefly exposing the quantum criticality of the TFIC, I will begin my journey with an inelastic neutron scattering experiment on CoNb₂O₆, which claims observation of evidence of E₈ physics in the material. Despite a ten-year gap, recent THz spectroscopy on the same material reignited our interest, leading us to challenge the E₈ paradigm and propose the picture. I will discuss why the physics provides a comprehensive understanding for the experimental observations. Along the course, we also surprisingly found long-life-time dark particle, a special kind of many-body magnetic excitation, in the integrable system which accommodates the physics. We will discuss how the dark particles are able to be prepared via another exotic soliton excitations in the system, and further propose a thermal activation detection of the lightest dark particle.

联系人/Contact：

理学院，朱老师，zhuyi48@westlake.edu.cn

Ms. Yi Zhu, School of Science, zhuyi48@westlake.edu.cn