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Mg and Nb-doped Mg films were deposited by rf magnetron sputtering. Morphological and structural analysis were performed by scanning electron microscopy and x-ray diffraction. The desorption kinetics has been investigated by using a Sievert-type apparatus. The overall activation energy and the reaction order controlling desorption are (141±5)kJmol−1H and n≈4 for Mg and (51±5)kJmol−1H and n≈1 for Nb-doped (5at.%) Mg. It is suggested that Nb atoms dispersed in the MgH2 grains catalyzes the dissociation of the hydride phase and that the rate limiting step in the H2 desorption is given by the H atomic migration through interconnected transformed domains of h-Mg.

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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