[Seminar] " Cavity quantum electrodynamics with magnons" by Prof. Jian-Qiang You
In this seminar, I will present the results achieved in my group on the cavity quantum electrodynamics with magnons, which involve an emerging new direction of research in both quantum optics and condensed matter physics. The first part of my talk focuses on the quantum coherence of magnons at both cryogenic and room temperatures, as well as the non-Hermitian physics of the cavity magnonics system consisting of magnons and cavity photons, including the observation of the exceptional point and the parity-time-symmetric phase transition. The second part focuses on the magnon Kerr effect in the cavity magnonics system and shows the observed bistability of magnon polaritons, where the bistable behaviors are emerged as sharp frequency switchings of the magnon polaritons and related to the transition between states with large and small number of polaritons. This cavity magnonics system provides a new platform to demonstrate various quantum-optics phenomena in a solid-state quantum system.
 D. Zhang, X. M. Wang, T. F. Li, X. Q. Luo, W. Wu, F. Nori, and J. Q. You, NPJ Quantum Information 1, 15014 (2015).
 D. Zhang, X. Q. Luo, Y. P. Wang, T. F. Li, and J. Q. You, Nat. Commun. 8, 1368 (2017).
 Y. P. Wang, G. Q. Zhang, D. Zhang, X. Q. Luo, W. Xiong, S. P. Wang, T. F. Li, C. M. Hu, and J. Q. You, Phys. Rev. B 94, 224410 (2016).
 Y. P. Wang, G. Q. Zhang, D. Zhang, T. F. Li, C. M. Hu, and J. Q. You, Phys. Rev. Lett. 120, 057202 (2018).
Jian-Qiang You is the Qiushi Professor of Physics at Zhejiang University. Before joining this University, he was a Chair Professor of Physics at Beijing Computational Science Research Center and had been the Xie Xide Professor of Physics at Fudan University in Shanghai and the Changjiang Professor of Physics, Chinese Ministry of Education. He received his Ph.D. in Condensed Matter Physics in 1997 at the Institute of Solid State Physics, Chinese Academy of Sciences, RIKEN Frontier Research System Grand Award in 2003, and the Distinguished Young Scholar Fund of the NSF of China in 2006. He was selected as the Leading Talent of “Ten Thousand Plan” (the National High-Level Talents Special Support Plan of China) in 2016. His research interests include quantum computation and quantum information, solid-state quantum optics, hybrid quantum systems, and mesoscopic physics. Currently, he is an Editorial Board member of Physical Review Applied and Quantum Information Processing.