Future quantum photonic networks require coherent optical memories for synchronizing quantum sources and gates of probabilistic nature. We demonstrate a fast ladder memory (FLAME) mapping the optical field onto the superposition between electronic orbitals of rubidium vapor. Using a ladder-level system of orbital transitions with nearly degenerate frequencies simultaneously enables high bandwidth, low noise, and long memory lifetime. We store and retrieve 1.7-ns-long pulses, containing 0.5 photons on average, and observe short-time external efficiency of 25%, memory lifetime (1/e) of 86 ns, and below 10^-4 added noise photons. Consequently, coupling this memory to a probabilistic source would enhance the on-demand photon generation probability by a factor of 12, the highest number yet reported for a noise-free, room temperature memory. This paves the way toward the controlled production of large quantum states of light from probabilistic photon sources.

中文翻译：

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用于室温下光子同步的快速、无噪声存储器。


未来的量子光子网络需要相干光学存储器来同步量子源和概率性质的门。我们展示了一种将光场映射到铷蒸气电子轨道之间叠加的快速梯形存储器（FLAME）。使用具有近简并频率的梯级轨道跃迁系统可同时实现高带宽、低噪声和长存储器寿命。我们存储和检索 1.7 ns 长的脉冲，平均包含 0.5 个光子，并观察到短时外部效率为 25%，存储器寿命 (1/ e ) 为 86 ns，并且添加的噪声光子低于 10 ^-4个。因此，将该存储器与概率源耦合将使按需光子生成概率提高 12 倍，这是迄今为止报告的无噪声室温存储器的最高数字。这为从概率光子源受控产生大量子态光铺平了道路。