High-Capacity Angularly-Multiplexed Holographic Memory Operating at the Single Photon Level

Abstract: We experimentally demonstrate an angularly-multiplexed holographic memory capable of intrinsic generation, storage and retrieval of multiple photons, based on off-resonant Raman interaction in warm rubidium-87 vapors. The memory capacity of up to 60 independent atomic spin-wave modes is evidenced by analyzing angular distributions of coincidences between Stokes and time-delayed anti-Stokes light, observed down to the level of single spin-wave excitation during several-$\mu$s memory lifetime. We also propose how to practically enhance rates of single and multiple photons generation by combining our multimode emissive memory with existing fast optical switches.