论文标题
单纳米颗粒通过波前塑形的受控光散射
Controlled light scattering of a single nanoparticle by wavefront shaping
论文作者
论文摘要
通过光子纳米结构以及纳米颗粒散射本身(包括MIE散射),通过纳米颗粒控制光散射对于对光的理解和控制至关重要。在这里,我们从理论上和数字上研究了通过波前形状来操纵纳米颗粒散射的可能性,这些可能最初开发出来,以控制纳米光介质中大量纳米颗粒散射的光。通过采用散射矩阵分析,我们发现即使是单个纳米颗粒也支持多个强烈散射的eigenchannels,这表明波前形状是操纵单个纳米颗粒的散射光的有前途的工具。通过发送形状的波前,我们可以选择性地激发特定型洋洋气,这是从不同的场分布中显而易见的。这些散射特征通道与散射器的不同谐振泄漏模式有关,该模式揭示了显着的局部“热点”,其中该场大大增强了。此外,我们研究了反向散射的光谱。要发送到与特定特征香水相关的波前,并观察到反向散射的光谱不仅揭示了激发通道,还揭示了其他几个。该结果表明,特征香水的存在短和远程光谱相关性。我们的工作提供了一种灵活的工具来操纵单个纳米颗粒的光散射,从而为纳米颗粒中的野外模式和光 - 物质相互作用打开了新的可能性,并探索了纳米颗粒散射的新特征,例如光谱相关性以及包括Mie Spheres在内的Nano散射剂的光散射的光谱和时间响应。
Controlling light scattering by nanoparticles is fundamentally important for the understanding and the control of light with photonic nanostructures, as well as for nanoparticle scattering itself, including Mie scattering. Here, we theoretically and numerically investigate the possibility to manipulate nanoparticle scattering by wavefront shaping that was initially developed to control light scattered by large numbers of nanoparticles in nanophotonic media. By employing a scattering matrix analysis, we find that even a single nanoparticle supports multiple strongly scattering eigenchannels, suggesting wavefront shaping as a promising tool to manipulate scattered light of a single nanoparticle. By sending in shaped wavefronts, we selectively excite eigenchannels, as is apparent from the distinct field distributions. These scattering eigenchannels are related to different resonant leaky modes of the scatterer, that reveal remarkable localized "hot spots" where the field is substantially enhanced. Moreover, we investigate the backscattered spectra; to this send in wavefronts relevant for a particular eigenchannel, and observe that the backscattered spectrum reveals not only the excited channel but also several others. This result points to the existence of short and long-range spectral correlations for an eigenchannel. Our work offers a flexible tool to manipulate light scattering of a single nanoparticle, and thus opens new possibilities to control field patterns and light-matter interactions in a nanoparticle, as well as to explore new features of nanoparticle scattering such as the spectral correlation and temporal response of light scattered by nano scatterers, including Mie spheres.