Fano Resonance Hybrid Waveguide-Coupled Plasmonic Sensor Using Transparent Conductive Oxide in the Near-Infrared Range

Photonics

Anum Khattak¹  Li Wei¹ 

[1] Department of Physics and Computer Science, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada;

关键词: planar waveguides;    optical sensors;    long-range surface plasmon resonance;    Fano resonance;    cadmium oxide;    mid-infrared;   

DOI  :  10.3390/photonics9030189

来源: DOAJ

【 摘 要 】

We proposed an ultra-sensitive refractive index sensor by using indium-doped cadmium oxide as a plasmonic material operating in near-infrared based on Fano resonance. The proposed sensor has a hybrid multilayer waveguide structure that supports both a long-range surface plasmon polariton (LRSPP) mode and a dielectric waveguide (DWG) mode. The design strategy of the structure parameters of the inner layers is elaborated in detail through the numerical analysis of the two modes. By suitably tailoring the thickness of the coupling layer, a strong mode coupling between the two modes could be achieved, leading to a sharp asymmetric Fano resonance. With the designed optimal physical parameters, our proposed sensor could achieve a maximum intensity sensitivity of 19,909 RIU⁻¹, a 193-fold enhancement than that of a conventional long-range SPR (LRSPR) based scheme. The proposed design can be a promising platform for biochemical sensing in the near-infrared region.

【 授权许可】

Unknown