The combination of semiconductor quantum dots with photonic cavities is a promising way to realize nonclassical light sources with state-of-the-art performances regarding brightness, indistinguishability, and repetition rate. Here we demonstrate the coupling of InGaAs/GaAs QDs emitting in the telecom O-band to a circular Bragg grating cavity. We demonstrate a broadband geometric extraction efficiency enhancement by investigating two emission lines under above-band excitation, inside and detuned from the cavity mode, respectively. In the first case, a Purcell enhancement of 4 is attained. For the latter case, an end-to-end brightness of 1.4% with a brightness at the first lens of 23% is achieved. Using p-shell pumping, a combination of high count rate with pure single-photon emission (g⁽²⁾(0) = 0.01 in saturation) is achieved. Finally, a good single-photon purity (g⁽²⁾(0) = 0.13) together with a high detector count rate of 191 kcps is demonstrated for a temperature of up to 77 K.

中文翻译：

---

基于圆形布拉格光栅中的量子点的电信O波段中明亮的赛尔增强型单光子源

半导体量子点与光子腔的结合是实现具有最先进的亮度、不可区分性和重复率性能的非经典光源的有前途的方法。在这里，我们演示了在电信 O 波段中发射的 InGaAs/GaAs QD 与圆形布拉格光栅腔的耦合。我们通过研究带上激发下的两条发射线，分别在腔模式内部和从腔模式失谐，证明了宽带几何提取效率的增强。在第一种情况下，获得了 4 的珀塞尔增强。对于后一种情况，端到端亮度为 1.4%，第一个镜头的亮度为 23%。使用 p 壳泵浦，结合高计数率和纯单光子发射 (g ⁽²⁾(0) = 0.01 饱和度）。最后，在高达 77 K 的温度下证明了良好的单光子纯度 (g ⁽²⁾ (0) = 0.13) 以及 191 kcps 的高探测器计数率。