Abstract

Quasi-phasematched frequency conversion in LiNbO₃ waveguides offers an efficient method for the generation of short wavelength radiation from infrared laser diodes. While different techniques have been used to form the ferroelectric domain grating necessary for quasi-phasematching, the annealed proton exchange (APE) process has been used exclusively to provide waveguide confinement Contradictory measurements of the nonlinear optical properties of proton exchange (PE) and APE-LiNbO₃ waveguides have been reported for several years.^1,2,3,4,5,6 The d₃₃ coefficient of PE-LiNbO₃ has been reported to be between 0^4,5 and 0.63³ the bulk LiNbO₃ value. No successful guided wave frequency conversion devices have been fabricated using unannealed PE waveguides.

© 1993 Optical Society of America