BLUE-LIGHT 2ND-HARMONIC GENERATION IN ION-IMPLANTED KNBO3 CHANNEL WAVE-GUIDES OF NEW DESIGN

We report phase-matched second-harmonic generation in KNbO3 channel wa veguides. The guides were fabricated by one single homogeneous He+ ion irradiation and specially structured photoresist on the KNbO3 crystal s serving as an implantation mask. The mask enabled the formation of c hannel guides with a trapezoidal-shaped cross section providing simult aneous confinement of both TE and TM modes. 2.6 mW second-harmonic blu e-light at 441 nm was generated in a 5.8-mm-long guide for an incident fundamental power of 280 mW. (C) 1996 American Institute of Physics.