Stack Daniel T, Lee Patricia J, Quraishi Qudsia
Opt Express. 2015 Mar 9;23(5):6822-32. doi: 10.1364/OE.23.006822.
The ability to filter unwanted light signals is critical to the operation of quantum memories based on neutral atom ensembles. Here we demonstrate an efficient frequency filter which uses a vapor cell filled with (85)Rb and a buffer gas to attenuate both residual laser light and noise photons by nearly two orders of magnitude with little loss to the single photons associated with our cold (87)Rb quantum memory. This simple, passive filter provides an additional 18 dB attenuation of our pump laser and erroneous spontaneous emissions for every 1 dB loss of the single photon signal. We show that the addition of a frequency filter increases the non-classical correlations and the retrieval efficiency of our quantum memory by ≈ 35%.
对于基于中性原子系综的量子存储器的运行而言，滤除不需要的光信号的能力至关重要。在此，我们展示了一种高效频率滤波器，它使用一个充满（85）Rb和缓冲气体的汽态室，将残余激光和噪声光子衰减近两个数量级，而与我们的冷（87）Rb量子存储器相关的单光子损失很小。这种简单的无源滤波器在单光子信号每损失1 dB的情况下，能额外对泵浦激光和错误的自发辐射提供18 dB的衰减。我们表明，添加频率滤波器可使我们量子存储器的非经典关联和检索效率提高约35%。
