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

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