报告题目：Probing
geometric phases in cold atomic topological bands

报 告 人：Lih-King Lim (Zhejiang University)

报告时间：1月3日（周四）上午10:00-11:00

报告地点：致远楼213

报告邀请人：王钢

报告摘要：Thanks
to recent progress in engineering topological band structures with cold atoms,
the accessible parameter regime of artificial crystal extends beyond that of
its solid-state counterpart. For example, the physics of 2D Dirac cones merging
as well as the 2D topological Haldane model were realized with cold atoms in
tunable optical lattices. Furthermore, cold atomic systems also open the door
for probing interesting geometric quantities which are otherwise difficult to
observe [1]. Specifically, we study the Landau-Zener processes in topological
bands with Bloch-oscillations-type experiment, realizing a Stuckelberg
interferometer. A new geometric phase shift is identified in the interference
fringes [2]. If time permits, we shall discuss our recent work on the winding
vector (rather than winding number) of Dirac points [3].

[1] T. Li et al, Science 352, 1094 (2016);
Tarnowski et al, Phys. Rev. Lett. 118, 240403 (2017).

[2] L.-K. Lim, J.-N. Fuchs, and G.
Montambaux, Phys. Rev. Lett. 112, 155302 (2014).

[3] G. Montambaux, et al, Phys. Rev. Lett.
121, 256402 (2018).

报告人简介：
Lih-King Lim obtained his PhD (2010) in Theoretical Physics from Utrecht
University, The Netherlands. He continued post-doctoral work (2010-2015) at LPS
and Institut d'Optique, CNRS, Orsay, France, and Max Planck Institute PKS,
Dresden, Germany. In 2015, he joined IAS Tsinghua University as an associate
member (faculty). Since 2018, he is assistant professor at the Institute of
Modern Physics, Department of Physics, Zhejiang University. His research
interests are theoretical studies of macroscopic manifestation of
topological/geometric effects in quantum materials, as realized in both cold
atomic and condensed matter systems. He has work on theoretical studies of
artificial gauge fields in cold atoms and its associated many-body effects,
Landau-Zener transitions in Dirac cone systems, as well as pseudospin models
for topological semimetals.