Research      Upcoming & past seminars

Online Colloquium: The nature of the Zeeman effect and field-induced topological semimetals

ABSTRACT

In the present talk, I will propose a new way to classify centrosymmetric metals by studying the Zeeman effect caused by an external magnetic field described by the momentum dependent g-factor tensor on the Fermi surfaces. Nontrivial U(1) Berry's phase and curvature can be generated once the otherwise degenerate Fermi surfaces are split by the Zeeman effect, which will be determined by both the intrinsic band structure and the structure of g-factor tensor on the manifold of the Fermi surfaces. Such Zeeman effect generated Berry's phase and curvature can lead to three important experimental effects, modification of spin-zero effect, Zeeman effect induced Fermi surface Chern number, and the in-plane anomalous Hall effect. By first-principal calculations, we study all these effects on two typical material, ZrTe5 and TaAs2, and the results are in good agreement with the existing experiments.

 

BIOGRAPHY

Professor Xi Dai obtained his Bachelor and Master’s degree (1993 &1996) from Zhejiang University and PhD (1999) from Institute of Theoretical Physics, CAS in China. After graduation, he did postdoctoral research in HKUST, Boston college and Rutgers University. From 2004-2007, he worked in University of Hong Kong as a research assistant professor. In 2007, he joined institute of physics, CAS as a professor in the theory division. In September 2017, he joined HKUST as a professor in the Department of Physics. Most of Prof. Dai’s previous research activities are concentrated in two fields: One is to develop computational methods for the electronic structure of the strongly correlated materials, and the other is to search for the topological non-trivial quantum state in realistic materials. Professor Dai received several important awards during the past ten years including the OCPA “Achievements in Asia Award” (2011), the CAS prize for outstanding scientific achievements and the KC Chou foundation “Fundamental Physics Prize” (2014). He is also a Fellow of American Physical Society (APS).  

 

Register in advance for this meeting:
https://cityu.zoom.us/meeting/register/tJcqce6vrj0oHdNpT0kdur3b-OwMmuKsWAYQ

After registering, you will receive a confirmation email containing information about joining the meeting.

*The information collected from you will be used solely for the purpose of processing your registration for the above online seminar.
Event Details
Speaker
Prof. Xi DAI
Chair Professor, Department of Physics, The Hong Kong University of Science and Technology

Date & Time
26 February 2021 3:00 PM

Venue
Zoom Meeting, City University of Hong Kong

Chair
Prof. Wei BAO
weibao@cityu.edu.hk