Colloquium
Department of Physics, NCU
When a photon meets many atoms: Cooperative Atom-Photon Interactions
Speaker
Prof. Ying-Cheng Chen (陳應誠)
Institute of Atomic and Molecular Sciences, Academia Sinica
Date 2019.05.14(Tue)
Time 14:00-16:00
Place S4-625
Light scattering or absorption in an atomic ensemble is actually a complicated many-body problem because it involves resonant dipole-dipole interactions (RDDIs) between atoms through exchange of photons, especially at a high atom density. Such cooperative atom-photon interaction may induce effects like shortening or lengthening of the spontaneous decay time (superradiance or subradiance) and shift of the energy level (cooperative Lamb shift). Although the formulation of cooperative atom-photon interactions are well established for many decades, thorough experimental tests of such physics have been revisited in recent years due to the well-control capability of cold atomic gases. In this talk, I will first introduce worldwide research status of this topic and then describe our research on cooperative radiation phenomena based on optically dense cold atomic ensembles. Applications in quantum information science, e.g. photonic quantum memory, to utilize and even design RDDIs in the platform of atom-waveguide or atomic arrays will be discussed.