Germanium self-assembled nanoislands and quantum dots are very prospective for CMOS-compatible optoelectronic integrated circuits but their photoluminescence (PL) intensity is still insufficient for many practical applications. Here, it is demonstrated experimentally that the PL of Ge nanoislands in silicon photonic crystal slabs (PCS) with hexagonal lattice can be dramatically enhanced due to the involvement in the emission process of the bounds states in the continuum. These high-Q photonic resonances allow to achieve PL resonant peaks with the quality factor as high as 2200 and with the peak PL enhancement factor of more than two orders of magnitude. The corresponding integrated PL enhancement is demonstrated to be more than one order of magnitude. This effect is studied theoretically by the Fourier modal method in the scattering matrix form. The symmetry of the quasi-normal guided modes in the PCS is described in terms of group theory. This work paves the way toward a new class of optoelectronic components compatible with silicon technology.

中文翻译：

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具有自组装Ge纳米岛的Si结构连续体中的光子束缚态

锗自组装纳米岛和量子点对于兼容 CMOS 的光电集成电路非常有前景，但它们的光致发光 (PL) 强度仍然不足以满足许多实际应用。在这里，实验证明，由于参与连续介质中的束缚态的发射过程，具有六方晶格的硅光子晶体板（PCS）中的 Ge 纳米岛的 PL 可以显着增强。这些高 Q 光子共振允许实现品质因数高达 2200 的 PL 共振峰和超过两个数量级的峰值 PL 增强因子。相应的集成 PL 增强被证明超过一个数量级。这种效应是通过傅立叶模态方法以散射矩阵形式进行理论研究的。PCS 中准法向导模的对称性是根据群论来描述的。这项工作为开发与硅技术兼容的新型光电元件铺平了道路。