Rare earth-activated 1-D photonic crystals were fabricated by RF-sputtering technique. The cavity is constituted by an Er3+-doped SiO2 active layer inserted between two Bragg reflectors consisting of ten pairs of SiO2/TiO2 layers. Scanning electron microscopy is employed to put in evidence the quality of the sample, the homogeneities of the layers thickness and the good adhesion among them. Near infrared transmittance and variable angle reflectance spectra confirm the presence of a stop band from 1500 nm to 2000 nm with a cavity resonance centered at 1749 nm at 0° and a quality factor of 890. The influence of the cavity on the ⁴I₁₃/₂ -->⁴I₁₅/₂ emission band of Er3+ ion is also demonstrated.

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The study of the differences between ordered and disordered materials (in the hundreds of nanometer length- scale) is a central topic for a better understanding of light transport phenomena in photonic media. In this work we report on an experimental and theoretical study of light transmission in disordered one dimensional photonic structures, where the disorder is introduced by a random variation of layer thicknesses. We found that the ran- dom photonic structure exhibits a dramatic decrease of the overall light transmission in the range 350–1200 nm with respect to the corresponding periodic photonic crystal. This study envisages the use of disordered one dimensional photonic structures for the realization of broad band filters for many applications, from sensing to photo- and thermo-voltaics

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