Tóm tắt: | Quantum memories capable of storing single photons are essential building blocks for quantum information processing, enabling the storage and transfer of quantum information over long distances [1]. Devices operating at room temperature can be deployed on a large scale and integrated into existing photonic networks, but so far warm quantum memories have been susceptible to noise at the single photon level [2]. Using a fundamentally different approach to quantum memories, i.e. the recently developed far off-resonant Raman memory scheme [3], we present a highly efficient room-temperature memory that is able to operate with a low unconditional noise floor in the quantum regime, something that no other room-temperature memory has been able to demonstrate before. The quantum memory is operated in warm caesium vapour, and the long-lived, 9.2 GHz hyperfine-split states of the caesium D2 line serve as ground and storage states. The laser fields are 15 GHz detuned from the excited state. © 2011 IEEE.
|