Laser diode-side-pumped high power 266 nm ultraviolet laser

An all-solid-state laser diode(LD)-side-pumped Nd:YAG ultraviolet(UV) laser at 266 nm is reported, which is based on fourth harmonic generation and adopts zigzag cavity structure. The type-Ⅰ critical phase matched LBO and BBO crystals are used as the second harmonic and fourth harmonic generation crystals, respectively, and 2.1 W UV laser of 266 nm with single pulse energy of 420 μJ is obtained at the pulse repetition rate of 5 kHz with the conversion efficiency of 13.13% from green to ultraviolet light. With V-shaped cavity configuration, only 305 mW 266 nm UV laser is obtained under the same condition.