Researchers realize coherent storage of light over one hour

Phys.org  May 10, 2021
One solution for remote quantum communication lies in quantum memories: photons are stored in long-lived quantum memory (quantum flash drive) and then quantum information is transmitted by the transportation of the quantum memory. Researchers in China adopted the spin wave atomic frequency comb (AFC) protocol in a ZEFOZ field (ZEFOZ-AFC) method to implement long-lived storage of light signals. They used dynamical decoupling to protect spin coherence and extend storage time. They demonstrated coherent storage of light in an atomic frequency comb memory over 1 hour with a fidelity of 96.4%. The study meets the basic requirements of the optical storage lifetime for quantum memories. Through optimizing storage efficiency and signal-to-noise ratios the researchers expect to transmit quantum information by classical carriers in a new quantum channel…read more. Open Access TECHNICAL ARTICLE 

Energy level diagram and experimental setup. Credit: MA Yu et al.