Ordinary and extraordinary refractive index profile characterization of single-mode proton-exchanged waveguides

A new method allowing the characterization of both the ordinary and extraor dinary refractive index profiles of single-mode proton-exchanged waveguides is presented and discussed. The method requires both TE and TM radiation m odes to be prism coupled into the waveguide, and the power carried by the r adiation modes to be measured as a function of the corresponding effective indices. Two sets of independent data corresponding to TE and TM polarizati on are thus obtained, which are sufficient to determine the optical paramet ers of the waveguide if a suitable least square fitting procedure is applie d. Experimental results are given, confirming the reliability of the method proposed. (C) 2001 Elsevier Science B.V. All rights reserved.