Physics Department - Interwoven Magnetic Kagome Metal Overcoming Geometric Frustration and NanoARPES Facility in SSRF

Physics Department - Interwoven Magnetic Kagome Metal Overcoming Geometric Frustration and NanoARPES Facility in SSRF
10:30am - 12:00pm
Room 4504, Academic Building, HKUST (Lifts 25-26)

Abstract
Magnetic kagome materials provide a unique platform for exploring magneto-transport phenomena, symmetry breaking, and charge ordering driven by the intricate interplay among electronic structure, topology, and magnetism. Herein, we introduce a new design strategy for interweaving quasi-1D magnetic Tb zigzag chains with nonmagnetic Ti-based kagome bilayers in TbTi3Bi4. Neutron diffraction, spin-polarized scanning tunneling spectroscopy, and angle-resolved photoemission spectroscopy analyses confirm that the interwoven structure exhibits a coexistent elliptical spiral magnetic order, a spin-density wave, and an unusually large band-folding gap. The combined unique magnetic and electronic state leads to a giant anomalous Hall conductivity of 10⁵ Ω¹cm¹. These results establish TbTi3Bi4 as a model system of magnetic kagome metals with strong electron–magnetic interactions [1]. I would also describe the construction, specifications, capabilities, and operation of BL07U—the NanoARPES endstation at the Shanghai Synchrotron Radiation Facility [2]. I will showcase our research on the electronic structure of emerging graphene devices, with a focus on moiré and flat bands [3] [4] [5].

References
[1] E. J. Cheng et al., arXiv: 2405.16831 (under review)
[2] H. Gao et al., Synchrotron Radiation News 37, 12-17 (2024)
[3] Y. W. Li et al., Advanced Materials 202205996 (2022)
[4] H. B. Xiao et al., Advanced Science 202412609 (2025)
[5] H. B. Xiao et al., Science Bulletin 70, 1030-1033 (2025)

Event Format
Speakers / Performers:
Prof. Zhongkai Liu
Shanghaitech University

Zhongkai Liu received B.S. in physics from Tsinghua University and Ph. D in Stanford University under the supervision of Prof. Zhi-Xun Shen. After one year working as a postdoc in I05, DLS, he started as an assistant/associate professor at ShanghaiTech University. His research interests lie in the photoemission study of topological quantum materials, low dimensional materials and development of synchrotron based spatial resolved ARPES. 

Recommended For
Faculty and staff, PG students
Language
English
Organizer
Department of Physics
Contact
Science & Technology