Manipulating the spontaneous emission rate of optical emitters with all-dielectric nanoparticles benefits from their low-loss nature and thus provides a relatively large extrinsic quantum yield. However, such Purcell effect greatly depends on the orientation of the dipole emitter. Here, we introduce the concept of isotropic magnetic Purcell effect with Purcell factors of about 300 and large extrinsic quantum yield (more than 80%) for a magnetic dipole emitter of arbitrary orientation in an asymmetric silicon nanocavity. The extrinsic quantum yield can even be boosted to nearly 100% by utilizing a GaP nanocavity. Isotropy of the Purcell factor is manifested via the orientation-independent emission of the magnetic dipole source. This isotropic Purcell effect is robust against small displacement of the emitter on the order of 10 nm, releasing the requirement of precise alignment in experiments.

中文翻译：

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各向同性磁珀塞尔效应

使用全介电纳米粒子操纵光发射器的自发发射速率得益于其低损耗特性，因此可提供相对较大的非本征量子产率。但是，这种赛尔效应很大程度上取决于偶极子发射器的方向。在这里，我们介绍各向同性磁珀塞尔效应的概念在不对称硅纳米腔中任意取向的磁偶极子发射极具有约300的赛尔因数和较大的外在量子产率（超过80％）。通过利用GaP纳米腔，外部量子产率甚至可以提高到近100％。珀塞尔因子的各向同性通过磁偶极子源的与方向无关的发射来体现。这种各向同性的赛尔效应对发射体的小位移（约10 nm）具有很强的抵抗力，从而释放了实验中精确对准的要求。