Er³⁺,Yb³⁺:glass-Co²⁺:MgAl₂O₄ diffusion bonded passively Q-switched laser

A Co²⁺:spinel passively Q-switched erbium-ytterbium-phosphate glass bonded laser pumped at 940 nm is reported. A pulse energy of 210 μJ, a peak power over 70 kW, and beam quality M² parameter of 1.2 are obtained under a pump power of 235 mW. An unbonded laser output experiment with the same dimension of the active material and the saturable absorber as the bonded laser output experiment is carried out. The reason why the output in the bonded laser is improved is determined.