Engineering the structural, plasmonic, and optical properties of multilayered aluminum-doped zinc oxide metamaterial grown by pulsed laser deposition

摘要

We engineer a tunable multilayered aluminum-doped zinc oxide metamaterial with low-loss and high-carrier concentration using the pulsed laser deposition. The results of the scanning probe microscopy study show excellent surface quality with a root mean square roughness value of 1.88 +/- 0.07 nm. The transmission electron microscopy measurements indicate a clear layer-by-layer structure of the multilayered samples. The optical permittivity results, obtained using the ellipsometry approach, show that the hyperbolic dispersion of the dielectric constant [Re (epsilon(parallel to)) > 0, Re (epsilon(perpendicular to)) < 0] is achieved in the near-IR spectral range. The low imaginary part of the optical permittivity Im (epsilon(perpendicular to)) = 0.003 and Im (epsilon(parallel to)) = 0.011 is achieved for the optimized sample at the epsilon-nearzero spectral point [Re (epsilon(perpendicular to)) = 0 at 1885 nm]. The results of the ellipsometry analysis show that the systematic variation of different fabrication conditions, such as the AZO/ZnO ratio, the thickness of an individual layer, the film's total thickness, and the deposition temperatures, allows for tuning the plasma frequency to omega(p) and damping frequency gamma(p) of the investigated samples, which is a promising approach for the future precise engineering of linear and nonlinear optical properties of multilayered aluminum-doped zinc oxide metamaterial. (C) 2019 Optical Society of America