Uniaxial indefinite material formed by helical-shaped wires

• Autor(es): Morgado, Tiago A. ; Maslovski, Stanislav I. ; Silveirinha, Mário G.
• Data: 2012
• Identificador Persistente: https://hdl.handle.net/10316/102723
• Origem: Estudo Geral - Universidade de Coimbra
• Tipo de Documento: Artigo científico
• Idioma: Inglês

Descrição

We demonstrate that a racemic array of helical-shaped metallic wires may be regarded as a local uniaxial epsilon-negative (ENG) material even when the metal conductivity is very large (e.g. in the microwave regime) and, as a result, enables strong negative refraction over a wide frequency range. Based on the negative refraction effect, we demonstrate partial focusing of p-polarized electromagnetic radiation using a planar lens formed by such a composite material. The results reported here are supported by full-wave simulations as well as by analytical calculations based on effective medium theory.