Space-dependent modeling of diode-pumped actively Q-switched lasers with considering lower level lifetime

With considering both the spatial distributions of the intracavity photon density and population inversion density and the lower level lifetime, the rate equations are obtained and solved numerically for diode-pumped actively Q-switched lasers. The effects of lower level lifetime on pulse rising time, falling time, width, peak power and energy are investigated. The lower level lifetime has no effect on pulse rising, falling and width. A larger value of the lower level time leads to smaller values of the pulse peak power and energy for a fixed pump condition. A more intensive pump leads to relatively lager effect of lower level lifetime on the pulse peak power and energy. The results can give a good understanding of the dependences of the laser pulse on the lower level time and be used to estimate the laser pulse characteristics of diode-pumped actively Q-switched lasers.