Annular-shaped beam for the mitigation of thermal lensing effects in Nd:YAG solid-state lasers

The present work aims to develop a model to mitigate the thermal lensing effects in laser diode-pumped solid-state laser systems. Using an annular-shaped beam, a virtual solid-state laser with a cylindrical form was simulated in double-end pumping geometry. At a pump ratio of (0.6), the results demonstrate that a pump light with an annular shape has an even better distribution for reducing the thermal lensing effect with a slope of 0.09 m −1 /W as compared to 0.07 m −1 /W slope for the top-hat distribution. Additionally, the annular-shaped pump beam provides the advantage of uniform pumping across the gain medium, which improves the overall efficiency and performance of the laser.