2004 Volume 32 Issue 4 Pages 277-281
This work presents a theoretical explanation and experimental evidence of pulses- intensity displacement and pulse- broadening profiles of a Q-switched and mode-locked Nd:YAG laser- pumped distributed feedback dye laser (DFDL). Experimental results followed by a theoretical simulation indicate that DFDL pulses peaked noticeably later than their corresponding Nd:YAG laser pulses. The DFDL pulse corresponding to the peak- power pump laser pulse occurs few pulses later than the expected location. The observed and simulated delays were found to depend upon the inter-pulse periods of the pumping Q-switched and mode-locked laser. We report the theoretical basis for the influence of temperature grating relaxation times on the dye laser's pulse characteristics, and apply the transient grating technique to measure the refractive index of a lasing dye solution. Results indicate that the thermal effects of preceding pulses integrate the gain for receding pulses. These results provide a good understanding of temperature grating relaxation times and their impact on the lasing characteristics of DFDL.
