Title: Detecting the Macroscopic Quantumness in Atomic Systems

Time: 1:20 PM, 03/11

Place: NCTS (Lecture Room A, 4F, 3rd General Building). 

Dr. Chang-Hau Kuo, Department of Physics, NTHU

Abstract:

Atomic ensemble interacting with nonclassical light provides an interesting platform for exploring the quantum nature of macroscopic systems. In this talk we study the quantum dynamics of the timed Dicke state in a two-level atomic ensemble induced by the absorption of a single photon. Using the extended Leggett-Garg inequality and two types of quantum coherence witness, we explore the possibilities to identify the macroscopic quantumness in the timed Dicke state with a large number of atoms. In addition, we also investigate the quantumness in a three-level atomic system that stores a single photon. Our work shows that the extended Leggett-Garg inequality and quantum coherence witness may be exploited to probe the quantumness preserved in atomic quantum memory.