INVESTIGADORES
SCAFFARDI Lucia Beatriz
artículos
Título:
PHOTOTHERMAL ANALYSIS OF POLYMERIC DYE LASER MATERIALS EXCITED AT DIFFERENT PUMP RATES
Autor/es:
R. DUCHOWICZ; L. SCAFFARDI; A. COSTELA; I. GARCÍA MORENO; R. SASTRE; A. U. ACUÑA
Revista:
APPLIED OPTICS
Editorial:
OPTICAL SOC AMER
Referencias:
Lugar: Washington; Año: 2003 vol. 42 p. 1029 - 1035
ISSN:
0003-6935
Resumen:
The photothermal properties and heat diffusion of polymeric lasers, made up from solutions of Rhodamine6G in solid matrices of poly2-hydroxyethyl methacrylate with different amounts of the cross-linkingmonomer ethylene glycol dimethacrylate and copolymers of 2-hydroxyethyl methacrylate and methylmethacrylate have been studied through photothermal deflection spectroscopy. The heat load that isdue to the pumping process was quantified as a function of the pump excitation repetition frequency0.2510 Hz, determining the time-dependent temperature changes at different locations within thelaser matrix. A theoretical model, which reproduces these changes with high accuracy, was developedon the basis of the heat-diffusion equation of optically dense fluids. The observed thermal effects becameimportant 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 Jcm2were also analyzed. These effects originate, most likely, from a two-step photothermal mechanism.