title: On-demand superradiant conversion of atomic spin gratings into single photons with high efficiency.
abstract: We create quantized spin gratings by single-photon detection and convert them on demand into photons with retrieval efficiencies exceeding 40% (80%) for single (a few) quanta. We show that the collective conversion process, proceeding via superradiant emission into a moderate-finesse optical resonator, requires phase matching. The storage time of 3 micros in the cold-atom sample, as well as the peak retrieval efficiency, are likely limited by Doppler decoherence of the entangled state.
authors.affiliation: Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Adam T
authors.initials: AT
authors.lastname: Black
authors.forename: James K
authors.initials: JK
authors.lastname: Thompson
authors.forename: Vladan
authors.initials: V
authors.lastname: Vuletić