Laser-induced damage study of bonded material for a high-brightness laser system

In this work we evaluated the laser-induced damage threshold of the interface between two identical YAG crystals, bonded by an inter-layer assisted surface activated bonding method. The experimental results indicate slight damage threshold degradation for both single- and polycrystalline trivalent rear-earth (RE³⁺)-ion-doped YAG gain media in the sub-nanosecond pulse regime. Moreover, crystal annealing prior to damage testing could provide additional improvement for the laser damage threshold of the bulk and bonded interface.