We discuss photo-luminescence characteristics of CdSe core/shell quantum dots at cryogenic temperatures using a hybrid system of a single quantum dot and an optical nanofiber. The key point is to control the emission species of quantum dot to charged excitons, known as trions, which have superior characteristics to neutral excitons. We investigate the photocharging behavior for the quantum dots by varying the wavelength and intensity of irradiating laser light, and establish a method to create a permanently charged situation which lasts as long as the cryogenic temperature is maintained. The present photocharging method may open a new route to applying the CdSe quantum dots in quantum photonics, and the hybrid system of photocharged quantum-dot and optical nanofiber may readily be applicable to a fiber-in-line single-photon generator.

中文翻译：

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光学纳米纤维上低温下单个 CdSe 量子点的带电激子的发生控制

我们使用单个量子点和光学纳米纤维的混合系统讨论了 CdSe 核/壳量子点在低温下的光致发光特性。关键是控制量子点的发射种类为带电激子，称为三元，其具有优于中性激子的特性。我们通过改变照射激光的波长和强度来研究量子点的光充电行为，并建立了一种方法来创造一种只要保持低温就可以持续充电的永久充电状态。该光充电方法可能为CdSe量子点在量子光子学中的应用开辟了一条新途径，光充电量子点和光学纳米纤维的混合体系可以很容易地应用于光纤串联单光子发生器。