Single-longitudinal-mode operation and second-harmonic generation of Nd:YVO(4) microchip lasers

A single-mode output of 221 and 16 mW for the fundamental and second-harmonic light was obtained with the combination of a Nd:YVO(4) microchip laser and an intracavity KTP crystal. It was found that the beam size and laser power in a plano-plano cavity were dependent on the absorption coefficient of the laser medium and that the material that had a higher absorption coefficient produced higher output power and smaller beam size in the laser cavity. This means that Nd:YVO(4) is suitable not only for single-mode oscillation but also for efficient intracavity second-harmonic generation.