Intracavity second-harmonic generation with a periodically domain-inverted LiTaO(3) device

Efficient intracavity second-harmonic generation (SHG) based on a bulk-type quasi-phase-matched (QPM) SHG device in a LiTaO(3) crystal is demonstrated. The periodically domain-inverted regions were fabricated by a high-voltage application technique. The internal loss from the refractive-index change in the domain-inverted regions was reduced to less than 0.1% by an annealing technique. Intracavity frequency doubling of a Nd:YVO(4) laser with the QPM SHG device pumped by a laser diode was effected to generate 13-mW green light for a pump power of 130 mW without suffering transverse mode distortion from a photorefractive effect.