High Beam Quality and High Power Mode-locked Solid-state Laser for Photocathode Drive Laser System

Solid-state lasers with high power and high beam quality have important applications, such as the photocathode electron sources. The alignment accuracy of the laser cavity impacts the output stability and beam quality of the solid state laser. The alignment precision of the gain crystal is especially critical for laser resonator. This paper reports the development of a solid-state laser. The laser resonant cavity consists of a Nd:YVO 4 gain crystal, a 880 nm pump, and a semiconductor saturable absorber mirror (SESAM) for mode-locking. A specially designed crystal fixing frame with collimators with varying diameters are employed for the crystal alignment. This laser could produce 6 W of output power at 162.5 MHz of repetition rate. The beam quality M 2 is very close to 1.