Optimization of energetic parameters of passively Q-switched lasers

The paper presents optimization of energy and peak power of the pulse of la ser with a slow passive Q-switch. The excited states absorption (ESA) in ab sorber is included in an optimization process. Using the laser model descri bed it is possible to determine optimal values of unsaturated absorber tran smission and reflectivity of the output mirror as a function of the normali zed initial gain coefficient z and parameter alpha, characterizing the rati o of the absorption cross-section of nonlinear absorber to the emission cro ss-section of the laser medium. To optimize the passively Q-switched laser the charts and simple analytical formulas, presented in the paper, can be a pplied. As an example, optimization of energy and peak power of the pulse o f Nd:YAG laser, with Cr4+:YAG crystal as passive Q-switch, pumped by 100 W matrix of laser diodes is presented. It has been shown that for laser energ y optimization, ESA slightly changes the value of optimal unsaturated absor ber transmission and optimal reflectivity of the output mirror of the laser .