A new approach to evaluate temperature distribution and stress fracture within solid state lasers

This work presents a new approach to determine the maximum allowable pump power that causes fractures in solid-state lasers. By considering temperature-dependent-thermal conductivity, heat equation was solved and an analytical thermal model of laser diode double end-pumped cylindrical laser rod was deduced. Taking into account two unequal pump radii focused on each rod faces, the temperature distribution and thermal stresses components were calculated at the two end faces of the rod under top-hat pump profile. The results showed that at the maximum total pump power of 200 W (80 W on the right side and 120 W on the left side) the rod is subject to fracture.