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The synthesis, structural characterization, and amplified spontaneous emission spectroscopy of dye-scattering particles in inorganic medium based on Rhodamine 610-TiO2 nanoparticles confined in silica xerogel matrix have been reported. Optimum concentrations have been determined depending on the normal fluorescence spectra for laser dye, in order to provide amplification, and TiO2 nanoparticals as scatter center. Random Laser has been studied under second harmonic Nd: YAG laser excitation. At the optimum concentrations, the results show that the values of bandwidth at full width half-maximum (FWHM) and the threshold energy are about 11 nm and 3 mJ respectively. The scattered and amplified probe light has been collected on a PC-interfaced CCD camera system

A random laser (RL) based on organic Rhodamine 6G (R6G) laser-dye and TiO 2 suspended nanoparticles have been prepared with polymethylmethacrylate (PMMA) as a host. Both liquid and spray-coated homogeneous film samples of 22 µm -30 µm thickness range were use. Optimum concentrations have been determined depending on the normal fluorescence spectra which give evidence that the laser dye provides amplification and TiO 2 nanoparticles act as scatter center. At the optimum concentrations, results of the random laser (RL) under second harmonic Nd: YAG laser excitation show that the values of bandwidth at full width half-maximum (FWHM) and the threshold energy are about 8 nm and 3 mJ respectively, which represent the minimum value for the liquid samples in the current research. Correspondly, these values become 12 nm and 3 mJ for film sample. The broadening that can be attributed to the concentration quenching of a laser dye at high a concentration level has been observed.