Experimental realization of a multiplexed quantum memory with 225 individually accessible memory cells

TLDR

Multiplexed quantum memories with many individually addressable cells are essential for long‑distance quantum communication and networks. The study demonstrates a DLCZ‑type quantum memory comprising 225 individually accessible cells in a macroscopic atomic ensemble. The experiment shows that entanglement with flying optical qubits can be stored and later retrieved with high fidelity from any neighboring cell, marking a significant advance toward practical quantum repeaters.

Abstract

To realize long-distance quantum communication and quantum network, it is required to have multiplexed quantum memory with many memory cells. Each memory cell needs to be individually addressable and independently accessible. Here we report an experiment that realizes a multiplexed DLCZ-type quantum memory with 225 individually accessible memory cells in a macroscopic atomic ensemble. As a key element for quantum repeaters, we demonstrate that entanglement with flying optical qubits can be stored into any neighboring memory cells and read out after a programmable time with high fidelity. Experimental realization of a multiplexed quantum memory with many individually accessible memory cells and programmable control of its addressing and readout makes an important step for its application in quantum information technology.