Electromagnetic energy within coated spheres containing dispersive metamaterials

Autor(es)

Arruda, Tiago J. ^[1] ; Pinheiro, Felipe A. ^[2] ; Martinez, Alexandre S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Pret, BR-14040901 Ribeirao Preto - Brazil

^[2] Univ Fed Rio de Janeiro, Inst Fis, BR-21941972 Rio De Janeiro, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Optics; v. 14, n. 6 JUN 2012.
• Citações Web of Science: 12

Resumo

An exact expression is derived for the time-averaged electromagnetic energy within a magneto-dielectric coated sphere, which is irradiated by a plane and time-harmonic electromagnetic wave. Both the spherical shell and core are considered to be dispersive and lossy, with a realistic dispersion relation of an isotropic split-ring resonator metamaterial. We obtain analytical expressions for the stored electromagnetic energies inside the core and the shell separately and calculate their contributions to the total average energy density. The stored electromagnetic energy is calculated for two situations involving a metamaterial coated sphere: a dielectric shell and dispersive metamaterial core, and vice versa. An explicit relation between the stored energy and the optical absorption efficiency is also obtained. We show that the stored electromagnetic energy is an observable sensitive to field interferences responsible for the Fano effect. This result, together with the fact that the Fano effect is more likely to occur in metamaterials with negative refraction, suggest that our findings may be explored in applications. (AU)

• Processo FAPESP: 08/02069-0 - Espalhamento de ondas eletromagnéticas por esferas e cilindros magnéticos: confinamento e transporte de ondas no limite de pequenas partículas e independência da energia armazenada com relação à forma do centro espalhador
• Beneficiário: Tiago José Arruda
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 10/10052-0 - Energia interna e espalhamento de ondas eletromagnéticas por esferas ou cilindros: ressonâncias de Fano e suas aplicações a metamateriais
• Beneficiário: Tiago José Arruda
• Modalidade de apoio: Bolsas no Brasil - Doutorado