We propose a scheme to realize a single-photon diode and circulator using two waveguides chirally coupled to a five-level M -type atom. Two external control fields are introduced to drive the emitter. Non-reciprocal single-photon propagation can be completed in our scheme, which underpins the single-photon diode and circulator. The single-photon diode can work well at special frequency points of the incident photon simultaneously. We can modulate the Rabi frequencies and detunings of the control fields to satisfy various values of frequency points of the incident photon. In addition, the non-reciprocity of the photon propagation can be turned off or on when the control fields are turned off or on. A single-frequency filter can filter out a special frequency for the incident photon by adjusting the detunings of the control fields. The single-photon circulator can realize photon propagation in the pathways ##IMG## {$1\rightarrow 2,\; 2\rightarrow 3,\; 3\right...}

中文翻译：

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通过手性波导-发射极耦合可调谐单光子二极管和环行器

我们提出了一种使用两个与五级M型原子手性耦合的波导来实现单光子二极管和环行器的方案。引入了两个外部控制字段来驱动发射器。不可逆的单光子传播可以在我们的方案中完成，该方案支撑了单光子二极管和循环器。单光子二极管可以在入射光子的特定频率点同时工作。我们可以调制拉比频率和控制场的失谐，以满足入射光子频率点的各种值。另外，当控制场关闭或打开时，可以关闭或打开光子传播的不可逆性。单频滤波器可以通过调整控制场的失谐来滤除入射光子的特殊频率。单光子循环器可以实现光子在路径中的传播## IMG ## {$ 1 \ rightarrow 2，\; 2 \ rightarrow 3，\; 3 \ right ...}