Optics and Photonics Center, Moroccan Foundation for Advanced Science, Innovation and Research (MAScIR), Rabat 10100, Morocco.
Graduate School of Engineering, Kobe University, Kobe 657-8501, Japan.
Sci Rep. 2016 Sep 14;6:33144. doi: 10.1038/srep33144.
High-Q optical Fano resonances realized in a variety of plasmonic nanostructures and metamaterials are very much promising for the development of new potent photonic devices, such as optical sensors and switches. One of the key issues in the development is to establish ways to effectively modulate the Fano resonance by external perturbations. Dynamic tuning of the Fano resonance applying the mechanical stress and electric fields has already been demonstrated. Here, we demonstrate another way of tuning, i.e., photo-tuning of the Fano resonance. We use a simple metal-dielectric multilayer structure that exhibits a sharp Fano resonance originating from coupling between a surface plasmon polariton mode and a planar waveguide mode. Using a dielectric waveguide doped with azo dye molecules that undergo photoisomerization, we succeeded in shifting the Fano resonance thorough photo-modulation of the propagation constant of the waveguide mode. The present work demonstrates the feasibility of photo-tuning of the Fano resonance and opens a new avenue towards potential applications of the Fano resonance.
在各种等离子体纳米结构和超材料中实现的高 Q 值光学 Fano 共振非常有希望用于开发新的强大光子器件，例如光学传感器和开关。发展的关键问题之一是建立通过外部干扰有效调节 Fano 共振的方法。已经证明可以通过机械应力和电场来动态调节 Fano 共振。在这里，我们展示了另一种调节方法，即光调谐 Fano 共振。我们使用简单的金属-电介质多层结构，该结构表现出源自表面等离激元模式和平面波导模式之间耦合的尖锐 Fano 共振。通过掺杂经历光致异构化的偶氮染料分子的介电波导，我们成功地通过波导模式传播常数的光调制来移动 Fano 共振。本工作证明了光调谐 Fano 共振的可行性，并为 Fano 共振的潜在应用开辟了新途径。
