Optimization of room-temperature continuous-wave Cr4+: Y AG lasers: experiment and modeling

Abstract

Experimental and numerical methods were employed to investigate the influence of thermal effects in room-temperature continuous-wave Cr4+:YAG lasers. Pump saturation, laser threshold, and laser efficiency data were first analyzed by accounting for the temperature dependence of the fluorescence lifetime, pump-induced heating in the gain medium, excited-state absorption at the lasing wavelength, and saturation effects. Best-fit values of the absorption, emission, and excited-state absorption cross sections were determined to be 11.2x10(-19) cm(2), 0.47x10(-19) cm(2), and 0.093x10(-19) cm(2), respectively. Based on the best-fit cross-section values, numerical calculations show that the optimum crystal length and absorption coefficient are 2 cm and 0.56 cm(-1), respectively.