[Lecture] Topological phase transition and transport in nodal line semimetal


Title: Topological phase transition and transport in nodal line semimetal
Speaker: Prof. Wei Chen (Nanjing University of Aeronautics and Astronautics)
Venue:  Room 403, Liwu Building of Science and Technology, Wushan Campus
Time: May 16, Thursday, 10:00

Topological nodal line semimetals (NLSs) are characterized by the crossing of the conduction and valence bands along closed loops in the Brillouin zone, which carries a π Berry flux. The topological property of the bulk states results in unique drumhead-like surface states. In this talk, I will present our recent work on new topological phase and quantum transport in NLSs. I will first show that electron-electron interaction in the NLS with two drumhead-like surface states can drive the surface states into a surface Chern insulator. Then I will discuss interesting transport results of both the surface and bulk states of the NLSs. The surface states in a spin-orbit coupled NLS exhibit spin polarization and can induce resonant spin-flipped reflection, which provides a unique evidence of the surface states. For the bulk states, we find that the torus-shaped Fermi surface and encircled π Berry flux carried by the nodal loop result in a fascinating interplay between the effective dimensionality of electron diffusion and band topology, which may lead to 3D weak localization effect or 2D weak antilocalization effect.

Announced by the School of Physics and Optoelectronic