Abstract
The photothermal properties and heat diffusion of polymeric lasers, made up from solutions of Rhodamine 6G in solid matrices of poly(2-hydroxyethyl methacrylate) with different amounts of the cross-linking monomer ethylene glycol dimethacrylate and copolymers of 2-hydroxyethyl methacrylate and methyl methacrylate have been studied through photothermal deflection spectroscopy. The heat load that is due to the pumping process was quantified as a function of the pump excitation repetition frequency (0.25–10 Hz), determining the time-dependent temperature changes at different locations within the laser matrix. A theoretical model, which reproduces these changes with high accuracy, was developed on the basis of the heat-diffusion equation of optically dense fluids. The observed thermal effects became important for impairing the laser stability at pump repetition frequencies higher than 1 Hz. In addition, the irreversible optical changes produced in the laser matrices at high pump fluence values (>1 J/cm2) were also analyzed. These effects originate, most likely, from a two-step photothermal mechanism.
© 2003 Optical Society of America
Full Article | PDF ArticleMore Like This
Ricardo Duchowicz, Lucía B. Scaffardi, Angel Costela, Inmaculada García-Moreno, Roberto Sastre, and A. Ulises Acuña
Appl. Opt. 39(27) 4959-4963 (2000)
William J. Wadsworth, Shirin M. Giffin, Iain T. McKinnie, John C. Sharpe, Anthony D. Woolhouse, Timothy G. Haskell, and Gerald J. Smith
Appl. Opt. 38(12) 2504-2509 (1999)
I. García-Moreno, A. Costela, M. Pintado-Sierra, V. Martín, and R. Sastre
Opt. Express 17(15) 12777-12784 (2009)