Transparent Conductive Oxides as Near-IR Plasmonic Materials: The Case of Al-Doped ZnO Derivatives

Using first-principles calculations, we investigate the origin of near infrared plasmonic activity in Al:ZnO transparent conducting oxides. Our results predict realistic values for the plasma frequency and the free electron density as a function of the Al doping and in agreement with recent experimental results. We also provide a microscopic insight on the formation of surface-plasmon polaritons at the Al:ZnO/ZnO interfaces in terms of characteristic lengths that can be measured by experiments. The direct comparison with standard plasmonic metals underlines the promising capabilities of transparent conducting oxides as compact and low-loss plasmonics materials for optoelectronic applications and telecommunications.