Decoherence-free quantum memory for photonic state using atomic ensembles

摘要

Large scale quantum information processing requires stable and long-livedquantum memories. Here, using atom-photon entanglement, we propose anexperimentally feasible scheme to realize decoherence-free quantum memory withatomic ensembles, and show one of its applications, remote transfer of unknownquantum state, based on laser manipulation of atomic ensembles, photonic stateoperation through optical elements, and single-photon detection with moderateefficiency. The scheme, with inherent fault-tolerance to the practical noiseand imperfections, allows one to retrieve the information in the memory forfurther quantum information processing within the reach of current technology.