Seminar：Properties of Topological semimetals: Chiral magnetic effect and instability under magnetic field

Xi Dai

Physics Department, Hong Kong University of Science and Technology

 

Time: 16:00-17:00pm, Friday, Feb. 2, 2018

Location:Room 242, East 4, ZijingangCampus, Zhejiang University

 

Abstract

In the present talk, I will introduce two important physical properties of topological semimetals. The first one is the chiral magnetic effect, which is the direct consequence of the presence of Weyl points in the band structures. I will introduce that the chiral magnetic effect can be detected by its coupling to certain phonon modes, which behave like pseudo scalars under point group transformations. Such coupling can generate resonance between the intrinsic plasmon oscillation and the corresponding phonon modes, leading to dramatic modification of the optical response by the external magnetic field. The second one is the instability of topological semimetal phase under strong magnetic field. In Dirac semi-metal, the quantum limit can be easily reached under the magnetic field leading to two types of phase instability caused by the high degeneracy of the topological zeroth Landau bands (LBs), namely the charge density wave (CDW) phase and polarized nematic phase formed by exciton condensation.  We also propose that both the DC transport measurement and Raman scattering can be used to distinguish the above two phases.

 

About the speaker

EDUCATION

Zhejiang University, China                                 B.S. Engineering                      1993

Zhejiang University, China                                 M.S. Physics                            1996

Institute of Theoretical Physics, CAS, China         Ph.D. Physics                          1999

APPOINTMENTS

Professor                                       Hong Kong University of Sci. & Tech.             since 2017.10

CAS Distinguished professor            Institute of Physics, CAS                               2015-2017

Joint professor                               College of Physical Science, UCAS                  2014-2017

Professor                                       Institute of Physics, CAS                               2007-2017

Research assistant professor            Hong Kong University                                  2004-2007

Postdoc                                         Rutgers Uni./ Boston College/HKUSTC            1999-2004  

                                    

AWARDS

Young Scientist Prize of Chinese Academy of Sciences                                    2011.6  

Qiushi group prize for science and technology                                               2011.9   

Distinguished Young Scientist Award of NSFC                                                2011.9

The CAS prize for outstanding scientific achievements                                    2012.1  

The OCPA “Achievements in Asia Award”                                                      2012.8  

The KC Chou foundation “Fundamental Physics Prize”                                    2014.5 

Listed as “Highly cited researchers” by Thomson Reuters                               2014-2016

Outstanding referees by APS journals                                                          2016

CITATIONS

Total citations on web of Science until 2018.1:    19395

h-index (based on web of science):                       53