Optical tunability of mid-IR based AZO nano geometries through the characterisation of plasmon induced resonance modes

The highly lossy nature of the conventional noble metals in the infrared region limits their implementation to the UV-Vis part of the electromagnetic spectrum. Hence, the necessity for a lossless alternate plasmonic material having large negative permittivity in the IR regime has paved the way for the exploration of transparent conducting oxides such as Aluminium doped Zinc Oxide. The mid-IR plasmonic response has a strong dependence on diverse tuneable parameters, the most efficient and flexible being the geometrical parameters. Detailed theoretical investigations using COMSOL Multiphysics can obliterate the requirement of complex fabrication efforts to understand the dynamic tunability of the optical signal. This study is motivated by the systematic investigation of the effect of shape factors on the linear optical properties of three different AZO based plasmonic planar nanostructures namely Nonamer, Dipole, and BowTie nanoantennas. A comparative matrix for various configuration sensitive optical modes investigated by this work provides a unique possibility to encompass the idea for exploration and design of mid-IR photodetection and sensor-based devices.