Speaker: Dr. Hsiang-Hua Jen, Institute of Atomic and Molecular Sciences, Academia Sinica 

Time: 1:20 p.m, 11/30, 2020

Place: R124, Department of Physics

Title: 
Localization of atomic excitation in a chirally coupled periodic atomic array

Abstract:
A periodic atomic chain with nonreciprocal couplings can be realized in an atom 
nanofiber or atom-waveguide interface. These quantum emitters present one of the 
strongly coupled systems that allow infinite-range dipole-dipole interactions induced 
by the guided modes. We theoretically study single excitation localization under a 
disordered potential.  By tuning the nonreciprocal couplings and the strengths of 
dipole-dipole interactions in the chirally coupled atomic system, we are able to 
identify the phase boundary from the delocalization to localization and an 
interaction-driven phase transition based on the measures of von Neumann entanglement 
entropy or level statistics. Our results present rich opportunities in studying 
nonequilibrium dynamics and pave the way toward  a potential application of quantum 
storage of light and many-body localization in open quantum systems.