Permittivity evaluation of multilayered hyperbolic metamaterials: Ellipsometry vs. reflectometry

• DOI: 10.1063/1.4914524
• Publication Date: 2015-03-11T17:00:12Z
• Authors: T. Tumkur; Y. Barnakov; S. T. Kee; M. A. Noginov; V. Liberman
• Keywords: Ellipsometry; Reflectometry; Homogenization

Metal-dielectric nanolaminates represent a class of hyperbolic metamaterials with uniaxial permittivity tensor. In this study, we critically compare extraction nanolaminate samples using two techniques: polarized reflectometry vs. spectroscopic anisotropic ellipsometry. Both Au/MgF2 and Ag/MgF2 metal-dielectric stacks are examined. We demonstrate the applicability treatment multilayered material as medium derived optical parameters to those expected from effective approximation. also experimentally effect varying outer layer on homogenization composite. Additionally, introduce simple empirical method extracting epsilon-near-zero point normal incidence reflectance. The results study useful in accurate determination ability tune its properties.