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Alumina porous ceramic with controlled pore size distribution was produced and its potential as a random laser host is investigated. Bi-chromatic random laser was observed from rhodamine B infiltrated ceramic when excited by 532 nm pulsed laser. Two random laser regimes were characterized and associated with the excitation of monomers and dimers. The results show that this class of material is very promising for the development of low-cost solid state random lasers.

Optimized conditions for the growth of lanthanoids orthoniobates (LnNbO 4 , Ln = lanthanide elements) single crystal minirods by a floating zone technique were investigated. Adequate atmospheres and pulling to feeding speed ratios to grow these materials were determined. Emphasis is given to the study of LaNbO 4 because of their more favorable growth conditions and crystalline quality. This material can be efficiently doped with rare earth elements such as erbium. It grows with high crystallinity and its preferential growth direction is [1 1 0]. A preliminary evaluation of optical properties of Er 3+ -doped LaNbO 4 single crystal under the JuddOfelt formalism indicates spectral parameters Ω t close and even larger than for Er 3+ ions in YVO 4 .

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