Light storage for one second in room-temperature alkali vapor

• DOI: 10.1038/s41467-018-04458-4
• Publication Date: 2018-05-21T13:23:11Z
• Authors: Or Katz; Ofer Firstenberg
• Keywords: Coherence time; Optical storage

Light storage, the controlled and reversible mapping of photons onto long-lived states matter [1], enables memory capability in optical quantum networks [2-6]. Prominent storage media are warm alkali gases due to their strong coupling spin [7,8]. In a dense gas, random atomic collisions dominate lifetime coherence, limiting time few milliseconds [9,10]. Here we present experimentally demonstrate scheme that is insensitive spin-exchange collisions, thus enabling long times at high densities. This unique property achieved by light field orientation within decoherence-free subspace states. We report on record 1 second cesium vapor, 100-fold improvement over existing schemes. Furthermore, our lays foundations for hour-long memories using rare-gas nuclear spins.