Effective medium theory for subwavelength cylinder arrays
1 State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University - Shanghai 200433, China
2 Department of Physics, Ningbo University - Ningbo, Zhejiang 315211, China
Received: 16 December 2015
Accepted: 24 February 2016
Based on the mode-expansion method under single-mode approximation, we obtained explicit expressions for the scattering coefficients of an array of subwavelength cylinders with general cross-sections and material properties. Mapping such an inhomogeneous system to an effective homogeneous medium exhibiting the same scattering coefficients, we established an effective medium theory for such a complex system. Our theory is justified by comparing with full wave simulations on realistic structures, and it is found to work well in a much more expanded parameter space than the standard Maxwell-Garnett theory.
PACS: 81.05.Xj – Metamaterials for chiral, bianisotropic and other complex media / 78.20.-e – Optical properties of bulk materials and thin films / 78.20.Ci – Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
© EPLA, 2016