Light storage for 150 milliseconds at room temperature

Or Katz, Ofer Firstenberg

Published Oct 18, 2017• 0 citations

Abstract

Light storage is the controlled and reversible mapping of light fields onto long-lived states of matter [1], forming the basis for quantum memories in optical quantum networks [2-6]. Prominent storage media are warm alkali gases due to their strong optical coupling and long-lived spin states [7-8]. In a dense gas, the random atomic collisions dominate the lifetime of the spin coherence, limiting the storage time to a few milliseconds [9-10]. Here we present and experimentally demonstrate a storage scheme that is insensitive to spin-exchange collisions, thus enabling long storage times at high atomic densities. This unique property is achieved by mapping the light field onto spin orientation, rather than onto higher spin moments. We report on a record storage lifetime for a warm system of 150 milliseconds (1/e) in cesium vapor. Furthermore, our scheme lays the foundations for hour-long quantum memories using rare-gas nuclear spins.

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