Liu Li, Wang Ruxue, Sun Yuwei, Jin Yi, Wu Aimin
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
Nanophotonics. 2023 Jun 15;12(15):3159-3164. doi: 10.1515/nanoph-2023-0195. eCollection 2023 Jul.
PbS colloidal quantum dots (CQDs) can be considered a promising lighting material, but their emission performance is mired by defect sites, strong photo-induced activity, and interaction with the environment. Here, we utilize periodic silicon metasurface sustaining a symmetry-protected bound state in the continuum to enhance the near-infrared emission of PbS CQDs at room temperature. In the experimental investigation, it is observed that the fluorescence of the coated PbS CQDs is enhanced by 10 times by the fabricated metasurface, and the emission peak has a quality factor up to 251 at wavelength 1408 nm. Meanwhile, the potential of this work in sensing is demonstrated by showing that the enhanced emission is disturbed by the introduction of sparse gold nanoparticles. In all, this work confirms that dielectric metasurfaces sustaining bound states in the continuum can be adopted to efficiently improve the emission performance of PbS CQDs which may find various practical applications including on-chip silicon-based optical sources and integrated sensors.
硫化铅胶体量子点（CQDs）可被视为一种很有前景的发光材料，但其发光性能受到缺陷位点、强烈的光致活性以及与环境相互作用的影响。在此，我们利用在连续谱中支持对称保护束缚态的周期性硅超表面，来增强室温下硫化铅CQDs的近红外发射。在实验研究中，观察到所制备的超表面使包覆的硫化铅CQDs的荧光增强了10倍，并且在波长1408nm处发射峰的品质因数高达251。同时，通过表明引入稀疏金纳米颗粒会干扰增强发射，证明了这项工作在传感方面的潜力。总之，这项工作证实了支持连续谱中束缚态的介电超表面可用于有效改善硫化铅CQDs的发光性能，这可能会有各种实际应用，包括片上硅基光源和集成传感器。
