Joint Seminar “Neutron Spectroscopy Studies on Kitaev Quantum Magnets” by Prof Jinsheng Wen on Monday, Dec 9, 2024 11am MW103, HKU

Prof. Jinsheng WEN
Nanjing University

The Kitaev model is an exactly solvable quantum-spin-liquid model defined on a honeycomb lattice with S = 1/2. The key element underlying this model is the bond-anisotropic Kitaev interaction. However, in a spin-only system, it is unrealistic to have such anisotropic interactions. In this talk, the speaker will show that the Kitaev interaction can be realized in a Mott insulator α-RuCl3, which has an effective spin of 1/2 by entangling the spin and orbital degrees of freedom. I will also show that by applying an in-plane magnetic field, the zigzag magnetic order ground state in α-RuCl3 can be completely suppressed, and a quantum-spin-liquid state can be induced. More recently, we extend the Kitaev physics to higher-spin system, where we find in a honeycomb-lattice antiferromagnet Na3Ni2BiO6 that there is a profound 1/3 magnetization plateau, which is stabilized by the Kitaev interaction, as evidenced from the neutron spectroscopy. This will also be discussed in the presentation.

HK Institute of Quantum Science & Technology,
Room525, Chong Yuet Ming Physics Building, The University of Hong Kong
Phone: 3917 1108

Anyone interested is welcome to attend.