Thermal Radiation in Photonic Crystals
E.L. Albuquerque, L.R. da Silva
Keywords: photonic crystals, optical filters, qusiperiodic structures
Abstract:Materials with simultaneously negative permittivity and negative permeability yielding a negative refractive index, the so-called negative index materials (NIMs) or metamaterials, have recently been extensively studied in several distinct artificial physical settings. However, until recently, no comprehensive analysis of the influence of the metamaterial to the thermal radiation distribution appeared in the scientific literature. In order to fill this gap, we study in this work the behavior of a light beam normally and obliquely incident on a one-dimensional multilayer photonic structure, composed of SiO2 / metamaterial layers arranged in a quasiperiodical fashion, which follows the Fibonacci (FB), Thue-Morse (TM), and double-period (DP) substitutional sequences. They can be used to enhance, suppress or attenuate spontaneous emission in all or certain directions by changing the density of modes, and therefore behaving as optical filters for modification of Planck’s blackbody spectrum. Our theoretical model is based on Kirchoff’s second law to calculate the emission spectra of the thermal radiation in these multilayered structures, together with a transfer matrix formalism, which simplify enormously the algebra involved in the calculation.