Time: 14:00, Jan. 11, 2022

Online Meeting URL: https://meeting.tencent.com/dm/hsZicZ5Szi4p

腾讯会议 (Tencent meeting ID): 614-608-070

Speaker: Prof. Gang Chen (The University of Hong Kong)

Abstract:

I will first talk about the interplay between the surface magnetism and time reversal symmetry protected Dirac electrons on the surface of 3d topological insulator. In addition to the simple ferromagnetism, there exist other competing magnetic states that include spiral antiferromagnets and skyrmion lattice. We further show that the novel magnetic structure feeds back to the itinerant electrons on the surface, generating distinct electron structures and surface states. I will then discuss the surface fractionalization in a 3d cluster Mott insulator. It is observed that, the surface generates local moments in an anomalous fashion and these moments could lead to exotic fractionalized spin liquid states.

References:

wisted magnetic topological insulators, CK Li, XP Yao, G Chen, Phys. Rev. Research 3, 033156 (2021)

Fractionalization on the surface: Is type-II terminated 1T-TaS2 surface an anomalously realized spin liquid?, CK Li, XP Yao, JP Liu, G Chen, arxiv preprint 2109.08093