Determination of threshold random gain medium in dye: Polymer films containing TiO₂ nanoparticles

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.

DOI: 10.4236/ns.2012.46055                

Abstract

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.

Keywords

Random Gain Medium; Random Laser; Internal Resonator

Conflicts of Interest

The authors declare no conflicts of interest.

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