Quantum Communication between Multiplexed Atomic Quantum Memories

The use of multiplexed atomic quantum memories (MAQM) can significantly enhance the efficiency to establish entanglement in a quantum network. In the previous experiments, individual elements of a quantum network, such as the generation, storage, and transmission of quantum entanglement have been demonstrated separately. Here we report an experiment to show the compatibility and integration of these basic operations. Specifically, we generate photon-atom entanglement from any chosen pair of memory cells in a 6 x 5 MAQM, convert the spin-wave to time-bin photonic excitation after a controllable storage time, and then store and retrieve the photon in a second MAQM for another controllable storage time. The preservation of quantum information in this process is verified by measuring the state fidelity. We also demonstrate that higher dimension quantum states can be transferred between the two distant MAQMs.