A cyclic atomic level scheme interacting with an optical and a microwave field is proposed for the generation and group-delay control of few-photon optical pulses. Our analysis exploits a hybrid second order-nonlinearity under conditions of electromagnetically induced transparency to generate an optical pulse. The generated pulse can be delayed or advanced through microwave intensity control of the absolute phase of the second-order-nonlinearity. Importantly, this handle on group delay of the generated pulse is number density-independent. Our scheme is thus ideally suited for the generation and control of few-photon optical pulses using ultra-dilute atomic samples. Our results will enable microscopic atomic interface systems that serve as controllable delay channels for both classical and quantum signal processing.

中文翻译：

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微波驱动的超稀薄原子团的光脉冲产生和群时延控制

提出了一种与光场和微波场相互作用的循环原子能级方案，用于几光子光脉冲的产生和群时延控制。我们的分析在电磁感应的透明性条件下利用混合二阶非线性来产生光脉冲。可以通过对二阶非线性的绝对相位进行微波强度控制来延迟或提前生成脉冲。重要的是，这种对生成脉冲的群时延的处理与数密度无关。因此，我们的方案非常适合使用超稀原子样本生成和控制几个光子的光脉冲。我们的结果将使微观原子接口系统成为经典和量子信号处理的可控延迟通道。