In this work, the equivalent Herpin index and phase thickness of a symmetrical film stack that consists of a dielectric film D and a metal film M are analyzed using the film matrix method. Five-layered symmetrical MDMDM film stacks in which the thickness of each film is less than 1/10 of the incident wavelength are utilized. The positive real part of the equivalent Herpin index and the negative real part of the phase thickness result in a negative real part of the equivalent refractive index. The range of refractive indices of D and M that lead to a negative refractive index of the overall material is developed as a procedure. When a p-polarized light wave obliquely propagates into the material with the negative refractive index, negative refraction and backward wave propagation occur. To reduce the loss in the negative index metamaterial, a porous metal film is introduced as a substitute for the metal film M in MDMDM to increase the feasibility of the use of the metamaterial as an optical coating.

Date Published: 27 August 2014
PDF: 9 pages
Proc. SPIE 9172, Nanostructured Thin Films VII, 917204 (27 August 2014); doi: 10.1117/12.2062474

Published in SPIE Proceedings Vol. 9172:
Nanostructured Thin Films VII
Akhlesh Lakhtakia; Tom G. Mackay; Motofumi Suzuki, Editor(s)