Abstract Multi-resonant plasmonic simple geometries like nanocylinders and nanorods are highly interesting for two-photon photoluminescence and second harmonic generation applications, due to their easy fabrication and reproducibility in comparison with complex multi-resonant systems like dimers or nanoclusters. We demonstrate experimentally that by using a simple gold nanocylinder we can achieve a double resonantly enhanced two-photon photoluminescence of quantum dots, by matching the excitation wavelength of the quantum dots with a dipolar plasmon mode, while the emission is coupled with a radiative quadrupolar mode. We establish a method to separate experimentally the enhancement factor at the excitation and at the emission wavelengths for this double resonant system. The sensitivity of the spectral positions of the dipolar and quadrupolar plasmon resonances to the ellipticity of the nanocylinders and its impact on the two-photon photoluminescence enhancement are discussed.

中文翻译：

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金纳米圆柱的多共振特性辅助增强双光子光致发光

摘要 像纳米圆柱和纳米棒这样的多谐振等离子体简单几何结构对于双光子光致发光和二次谐波产生应用非常有趣，因为与复杂的多谐振系统（如二聚体或纳米团簇）相比，它们易于制造和重现。我们通过实验证明，通过使用简单的金纳米圆柱体，我们可以通过将量子点的激发波长与偶极等离子体模式匹配，同时发射与辐射四极模式耦合来实现量子点的双共振增强双光子光致发光. 我们建立了一种方法来实验分离该双谐振系统的激发波长和发射波长处的增强因子。