Blue light generation by frequency doubling CW diode laser radiation in KNbO ₃ channel waveguides

Abstract

Blue light at 430 nm is generated by frequency doubling CW AlGaAs diode lasers in ion-implanted KNbO3 channel waveguides. Stable Cerenkov-type second harmonic generation is demonstrated at room temperature without the need for precise temperature control. With 97 mW of fundamental power in a channel guide of 5.6 mm length a blue light output power of 1.1 mW is achieved. Efficiencies of more than 40%/W cm are obtained by adding up the contributions from several modes of the multimode waveguide.