Laboratoire de Spectrométrie Ionique et Moléculaire (LASIM), Université Claude Bernard Lyon 1 - CNRS (UMR 5579), Bâtiment A. Kastler, 43 Boulevard du 11 novembre 1918, 69622 Villleurbanne, France.
Phys Rev Lett. 2010 Aug 13;105(7):077401. doi: 10.1103/PhysRevLett.105.077401. Epub 2010 Aug 10.
Optical second-harmonic generation from gold nanoparticles is investigated both experimentally and theoretically. The contribution of octupoles is reported for the first time in the second-harmonic emission pattern, by using an harmonic polarization in the scattering plane. The experimental results presented here for particle sizes up to 100 nm are in excellent agreement with finite element method simulations involving the normal surface term only in the nonlinear polarization source. In addition, analytical calculations based on nonlinear Mie scattering theory clearly evidence the constructive and destructive interferences occurring between the dipolar and octupolar responses selected with this polarization configuration.
实验和理论研究了金纳米粒子的光学二次谐波产生。首次在二次谐波发射模式中报道了八极子的贡献，方法是在散射平面中使用谐和偏振。本文给出的粒径高达 100nm 的实验结果与仅在非线性极化源中包含法向面项的有限元方法模拟非常吻合。此外，基于非线性 Mie 散射理论的分析计算清楚地表明了在这种极化配置下选择的偶极子和八极子响应之间发生的建设性和破坏性干涉。
