Observation of Fano-Type Interference in a Coupled Cavity-Atom System
Yong Cheng1,2,3, Zheng Tan1,2**, Jin Wang1,2, Yi-Fu Zhu4, Ming-Sheng Zhan1,2
1State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 2Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071 3University of Chinese Academy of Sciences, Beijing 100049 4Department of Physics, Florida International University, Miami 33199, USA
We present the experimental observation of the Fano-type interference in a coupled cavity-atom system by confining the laser-cooled $^{85}$Rb atoms in an optical cavity. The asymmetric Fano profile is obtained through quantum interference in a three-level atomic system coherently coupled to a single mode cavity field. The observed Fano profile can be explained by the interference between the intra-cavity dark state and the polariton state of the coupled cavity–atom system. The possible applications of our observations include all-optical switching, optical sensing and narrow band optical filters.