Wavelength-dependent diffusion conditions of nickel-indiffused LiNbO3 optical waveguides

The effects of the diffusion conditions on die polarization states and opti cal confinement of Ni:LiNbO3 waveguides have, for the first time, been succ essfully investigated and proven to be informative. Accordingly, a simple r ule corresponding to the wavelength-dependent diffusion conditions for the Ni:LiNbO3 waveguides has been proposed. It has been proven that a diffusion temperature higher than 800 degrees C is suitable for the fabrication of N i-indiffused waveguides at a 1.3 mu m wavelength, while a temperature aroun d 800 degrees C is suitable at a 0.6328 mu m wavelength. Following this rul e, further demonstrations have also been completed through the fabrication and measurement of Mach-Zehnder modulators at these two different wavelengt hs. (C) 1999 John Wiley & Sons, Inc.