Title: Neutron spectroscopy on quantum magnetism

Speaker: Jinsheng Wen

Time&Location: 12:00PM, Oct. 25, Room 501, Tangzhongying Building

Abstract:

Magnetism is an old but forever young topic. Typically, magnetic systems will be ordered at low temperatures, and can be described by classical theory. However, by introducing magnetic frustration which enhances quantum fluctuations, magnetic systems will exhibit quantum behaviors, whose description is beyond conventional theory. The magnetism is discussed in terms of quantum magnetism, covering various novel quantum spin states such as quantum spin liquids, and novel excitations such as fractional spin excitations. In this talk, I will introduce how we use state-of-the-art neutron spectroscopy technique to study the quantum magnetism in several quantum magnets. For instance, in a proximate Kitaev quantum spin liquid candidate α-RuCl₃, we have realized the Kitaev interaction, and induced a quantum spin liquid state by applying a magnetic field; in a van der Waals ferromagnet, we have found the dual nature of the magnetic excitations and the Kondo coupling between local moments and itinerant electrons.

Biography:

Jinsheng Wen is a Professor of Physics at the School of Physics in Nanjing University. Prof. Wen got his Bachelor’s degree from Tsing University in 2005, and PhD from Stony Brook University in 2010. From 2010 to 2012, he did postdoc at University of California at Berkeley, and since 2013 he has been appointed as a full professor by Nanjing University. He has been committed to the study strongly correlated electronic systems including high-temperature superconductors and quantum spin liquids using neutron spectroscopy. In recent years, his group has found several novel quantum spin states and unconventional excitations. Based on these results, they published 4 ESI highly cited papers in PRL, 3 Nature Communications, and 1 PRX. He has won numerous awards and honors, including National Science Fund for Distinguished Young Scholars in 2022, Jiangsu Provincial Science and Technology Medal for Young Scientists and Jiangsu Distinguished Young Physicists Prize in 2020, and National Science Fund for Excellent Young Scholars and Distinguished Young Scholars of Jiangsu Natural Science Foundation in 2018.