Fabrication of strip loaded outdiffusion guides on lithium niobate substrate

Abstract

A fabrication method of strip‐loaded waveguide on lithium outdiffused lithium niobate substrate is presented. The fabricated waveguide provides good characteristics, such as single transverse magnetic (TM) or electric (TE) polarization and without having a thick surface guide on the substrate. Also it takes less time to fabricate the waveguide, and hence, less damage on the substrate is expected. A numerical simulation shows that the normalized amplitude contours of the fundamental waveguide mode can be expanded for efficient fiber coupling or condensed for enhancing the electro‐optic effect depending on the refractive index of the loaded strip. The output power profile of the waveguide, detected by a linear array of charge coupled devices, is in good agreement with that calculated numerically. © 1992 John Wiley & Sons, Inc.