Optical metamaterials with different metals

TL;DR

This study compares different metals in optical fishnet metamaterials, highlighting silver's superior performance for negative permeability resonance and providing guidance for optimized design.

Contribution

It demonstrates the importance of using experimentally measured dielectric functions over the Drude model for accurate predictions in optical metamaterials.

Findings

Silver yields the strongest negative-permeability resonance.

Silver-based metamaterials have the highest figure-of-merit.

Experimental dielectric data improves modeling accuracy.

Abstract

We investigate the influence of different metals on the electromagnetic response of fishnet metamaterials in the optical regime.We found, instead of using a Drude model, metals with a dielectric function from experimentally measured data should be applied to correctly predict the behavior of optical metamaterials. Through comparison of the performance for fishnet metamaterials made with different metals (i.e., gold, copper, and silver), we found silver is the best choice for the metallic parts compared to other metals, because silver allows for the strongest negative-permeability resonance and, hence, for optical fishnet metamaterials with a high figure-of-merit. Our study offers a valuable reference in the designs for optical metamaterials with optimized properties.