Radiative cascades emit correlated photon pairs, providing a pathway for the generation of entangled photons. The realization of a radiative cascade with impurity atoms in semiconductors, a leading platform for the generation of quantum light, would therefore provide a new avenue for the development of entangled photon pair sources. Here we demonstrate a radiative cascade from the decay of a biexciton at an impurity–atom complex in a ZnSe quantum well. The emitted photons show clear temporal correlations revealing the time-ordering of the cascade. Our result establishes impurity atoms in ZnSe as a potential platform for photonic quantum technologies using radiative cascades.

中文翻译：

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ZnSe 中空间局域双激子的级联光子之间的相关性

辐射级联发射相关光子对，为纠缠光子的产生提供了途径。因此，在半导体中实现与杂质原子的辐射级联是产生量子光的领先平台，将为纠缠光子对源的发展提供新途径。在这里，我们展示了 ZnSe 量子阱中杂质原子复合物处双激子衰变的辐射级联。发射的光子显示出清晰的时间相关性，揭示了级联的时间顺序。我们的结果确立了 ZnSe 中的杂质原子作为使用辐射级联的光子量子技术的潜在平台。