Extraction of Modeling Parameters for Low-loss Alternative Plasmonic Material

AbstractPlasmonics is a revolutionary branch of photonics which offers the benefit of both nanoscale electronics and broadband photonics by coupling the photon energy and momentum to free electron gas on the surface of metals generating a quasi-particle wave known as surface plasmon which enables the manipulation of light at the nanoscale. Though metals are the basic building blocks of plasmonic devices, they are blighted by high resistive losses at optical frequencies which restrict the development of surface plasmon based devices. This calls for the development of alternative materials for plasmonic applications. Transparent conducting oxides such as aluminum zinc oxide (AZO) and gallium zinc oxide (GZO) behave like metals in the near Infra-Red region which enables the application of these materials as alternatives to metals in plasmonic devices. The advantages include low intrinsic loss, tunability, compatibility with semi-conductor based design and fabrication methods etc. In order to simulate the performance of these materials as plasmonic materials, the modeling parameters need to be found out. In this paper we report the Drude and Lorentz model parameters for AZO and GZO. The modeling parameters have been extracted using a nonlinear optimization algorithm. In order to validate the optimized parameters we have determined the complex relative permittivity using the extracted parameters and compared them with the experimental results and an excellent agreement has been found. The root-mean-square (RMS) deviations are found to be as little as 0.0259 and 0.0479 for Drude model and 0.0680 and 0.0587 for Lorentz model respectively for AZO and GZO. It is expected that the modeling parameters will be of great use to the plasmonics research community for the development of new devices