Author(s)

Baha T. Chiad, Mohammed A. Hameed, Firas J. Kadhim, Kamil H. Latif

Department of Physics, College of Science, University of Baghdad, Baghdad, Iraq.
Ministry of Environment, Baghdad, Iraq.

Random gain medium based on organic Rhodamine 590 (R590) laser-dye and Titanium dioxide (TiO2) suspended nanoparticles have been prepared with polymethylmethacrylate (PMMA) as a host. Spray-coated homogeneous film samples of 22.4 μm thickness. Optimum concentrations have been determined depending on the normal fluorescence spectra which give evidence that the laser dye provides amplification and TiO₂ nanoparticles act as scatter center. At the optimum concentrations, results of the random gain medium under second harmonic Nd: YAG laser excitation shows that the values of bandwidth at full width half-maximum (FWHM) and the threshold energy are about 11 nm and 10 mJ respectively.

Random Gain Medium; Random Laser; Internal Resonator

Chiad, B. , Hameed, M. , Kadhim, F. and Latif, K. (2012) Determination of threshold random gain medium in dye: Polymer films containing TiO₂ nanoparticles. Natural Science, 4, 402-408. doi: 10.4236/ns.2012.46055.