Tribelsky Michael I, Geffrin Jean-Michel, Litman Amelie, Eyraud Christelle, Moreno Fernando
1] Lomonosov Moscow State University, Russia [2] Moscow State University of Information Technologies, Radioengineering and Electronics MIREA, Moscow, Russia.
Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel UMR 7249, 13013 Marseille, France.
Sci Rep. 2015 Jul 23;5:12288. doi: 10.1038/srep12288.
The future of ultra-fast optical communication systems is inevitably connected with progress in optical circuits and nanoantennas. One of the key points of this progress is the creation of elementary components of optical devices with scattering diagrams tailored for redirecting the incident light in a desired manner. Here we demonstrate theoretically and experimentally that a small, simple, spatially homogeneous dielectric subwavelength sphere with a high refractive index and low losses (as some semiconductors in the visible or near infrared region) exhibits properties allowing to utilize it as a new multifunctional element for the mentioned devices. This can be achieved by taking advantage of the coherent effects between dipolar and multipolar modes, which produce anomalous scattering effects. The effects open a new way to control the directionality of the scattered light. The directional tuning can be obtained in a practical way just by a change in the frequency of the incident wave, and/or by a well-chosen diameter of the sphere. Dielectric nanoparticles with the required optical properties in the VIS-NIR may be now readily fabricated. These particles could be an efficient alternative to the widely discussed scattering units with a more complicated design.
超快光通信系统的未来不可避免地与光电路和纳米天线的进展相关联。这一进展的关键要点之一是创建具有定制散射图的光学器件基本组件，以便以期望的方式重定向入射光。在此，我们通过理论和实验证明，一个小的、简单的、空间均匀的具有高折射率和低损耗的介电亚波长球体（如可见光或近红外区域的某些半导体）展现出一些特性，使其能够用作上述器件的新型多功能元件。这可以通过利用偶极和多极模式之间的相干效应来实现，这些效应会产生异常散射效应。这些效应为控制散射光的方向性开辟了一条新途径。仅通过改变入射波的频率和/或通过精心选择球体的直径，就可以实际获得方向性调谐。如今，可以很容易地制造出在可见光 - 近红外区域具有所需光学特性的介电纳米颗粒。这些颗粒可能是设计更为复杂且被广泛讨论的散射单元的有效替代品。
