@inproceedings{5790406aab54427d9b7abb1123343884,
title = "Observation of nonlocal optical response in doped-cadmium-oxide epsilon-near-zero thin films",
abstract = "We study optically-excited nonlocalities in thin films of doped cadmium oxide. Although these effects are usually weak and hardly observable in the optical response of noble metals, the free-electron nonlocality is significantly increased in doped-cadmium-oside thin films. This increase is due mainly to: (i) low electron scattering rates; and (ii) interband transitions due to valence-band and inner-core electrons that occur far from the epsilon-near-zero frequency. The optical nonlocality manifests itself in the blueshift of the epsilon-near-zero mode, an associated reflectance dip, and the onset of higher-order modes. We model the structure using a generalized hydrodynamic theory that treats the free electrons in the film as a viscoelastic fluid. We demonstrate that both elasticity and viscosity play a significant role in the optical response of the film. The elasticity induces optical resonances associated with the longitudinal pressure modes of the free-electrons fluid, leading to a thickness-dependent permittivity. The viscosity introduces nonlocal damping and additional losses. In our view, this demonstration furthers our understanding of the dynamics of light-matter interactions, and adds a significant stepping stone toward the ability to effectively manipulate linear and nonlinear optical properties at the nanoscale.",
author = "{De Ceglia}, Domenico and Michael Scalora and Vincenti, {Maria A.} and Salvatore Campione and Kyle Kelley and Maria, {Jon Paul} and Keeler, {Gordon A.} and Luk, {Ting S.}",
note = "Publisher Copyright: {\textcopyright} 2017 IEEE.; 19th International Conference on Electromagnetics in Advanced Applications, ICEAA 2017 ; Conference date: 11-09-2017 Through 15-09-2017",
year = "2017",
month = oct,
day = "11",
doi = "10.1109/ICEAA.2017.8065557",
language = "English (US)",
series = "Proceedings of the 2017 19th International Conference on Electromagnetics in Advanced Applications, ICEAA 2017",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "1462--1464",
booktitle = "Proceedings of the 2017 19th International Conference on Electromagnetics in Advanced Applications, ICEAA 2017",
address = "United States",
}