Probing geometric phases in cold atomic topological bands

Title: Probing geometric phases in cold atomic topological bands

Speaker: Lih-King Lim

Location: Room 213, Zhiyuan Building

Time: 10:00-11:00p.m. Jan 3th, 2019

Abstract: 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.