Design criteria for mode size optimization in diode-pumped solid-state lasers

Based on space-dependent rate equation analysis, design and optimization criteria for the mode size of diode-pumped solid-state lasers are proposed, assuming an TEM/sub 00/ single transverse mode in the resonator and circular or elliptic Gaussian pump beam. The optimum ratio between mode and pump spot size increases with input power and ellipticity of the pump beam. Simple plots may be used as guidelines to determine, in addition to the optimum spot size, the corresponding laser threshold, slope efficiency, and expected output power. Experimental examples are given for an end-pumped Nd:YAG laser, showing good agreement with the design predictions. >