标题： 共振介质纳米颗粒与介质波导之间的光学耦合通过三次谐波生成显微镜进行探测 显示英文标题

标题： Optical coupling between resonant dielectric nanoparticles and dielectric waveguides probed by third harmonic generation microscopy

摘要： 亚波长全介质纳米颗粒的局域电磁模式和可忽略的欧姆损耗促成了对其日益增长的兴趣。 尽管有大量的研究探讨了全介质纳米结构与自由空间电磁场的相互作用，但它们作为集成光子学元件的性能仍未被解决。 我们进行了一项实验研究，通过三次谐波显微镜探测了共振亚波长硅纳米盘与非共振硅波导之间的光学耦合。 通过将纳米盘放置在距波导不同距离的位置，我们观察到三次谐波强度的调制因子高达4.5。 这种调制归因于纳米盘中局部场增强的变化，这是由于它们与波导的耦合以及随后对磁型共振的调制所致。 有趣的是，尽管波导为纳米盘提供了一个额外的损耗通道，但我们通过严格的全波模拟验证了纳米盘内局部场强度的增加。 这项工作朝着将全介质纳米颗粒集成到光子芯片上迈出了一步。 显示英文摘要

摘要： Localized electromagnetic modes and negligible Ohmic losses dictate the growing interest in subwavelength all-dielectric nanoparticles. Although an exhaustive volume of study dealt with interaction of all-dielectric nanostructures with free-space electromagnetic fields, their performance as integrated photonics elements remains untackled. We present an experimental study of optical coupling between a resonant subwavelength silicon nanodisk and a non-resonant silicon waveguide, as probed by third harmonic generation microscopy. By placing the nanodisks at different distances from the waveguide, we observe third harmonic intensity modulation by a factor of up to 4.5. This modulation is assigned to changes in the local field enhancement within the nanodisks caused by their coupling to the waveguides and subsequent modulation of their magnetic-type resonances. Interestingly, although the waveguide presents an additional loss channel for the nanodisk, we observe an increase in the local field strength within the nanodisk, as verified by rigorous full-wave simulations. This work makes a step toward integration of all-dielectric nanoparticles on photonic chips.