title: High efficiency photon counting using stored light.
abstract: We propose a method that can, in principle, achieve nearly ideal photon counting, by combining the techniques of photonic quantum memory and ion-trap quantum-state measurements. After mapping the quantum state of a propagating light pulse onto metastable collective excitations of a trapped cold atomic gas, it is possible to monitor the resonance fluorescence induced by an additional laser field that couples only to the metastable excited state. Even with a photon collection/detection efficiency as low as 10%, it is possible to achieve photon counting with efficiency exceeding 99%.
authors.affiliation: Department of Electrical and Computer Engineering, University of California, Santa Barbara 93106, USA.
authors.forename: A
authors.initials: A
authors.lastname: Imamoglu