Abstract

We have shown that gain of a dye laser amplifier depends on the wavelength of the probe pulse. The probe pulse for our experiment was obtained from a rhodamine (Rh) 590 coaxial dye laser. The input energy to the amplifier was 5 μJ and the pulse width of the coaxial laser was 0.5 μs. The amplifier stage consisted of a quartz planar waveguide cell, pumped by a standard flashlamp arrangement. The solution used in the amplifier stage was Rh 590 and MeOH at a concentration of 1 × 10⁻³ M/liter and cyclooctateyraene at a concentration of 0.1 M/liter. The flashlamp used in the amplifier stage had a 7-mm bore diam and had electrical connections to a 2-μF capacitor. The pulse width of the flashlamp used to achieve gain was 5 μs. Flashlamp intensity was calculated within a 510–550-nm wavelength region and ranged from 175 to 675 W/cm². The wavelength range of the probe pulse was 570–605 nm and the bandwidth of the tuned pulse was 5 nm. Because of the overlapping of the absorption and fluorescence spectra of Rh the best results occurred when the coaxial laser was tuned past the long-wavelength edge of the absorption band of Rh 590. Gain was less than one for peak wavelengths of probe pulses in the 570–580-nm range and approached two for peak wavelengths of 590–605 nm.

© 1986 Optical Society of America