Tomography of polaron luminescence in LiNbO3: application to the characterisation of optical guides and integrated optical devices

We propose in this paper a fast, sensitive and reliable technique of characterisation based on micro-spectroscopy (Raman and polaron luminescence), which allows at the determination of the chemical reduction profile after titanium diffusion or other high-temperature annealing treatments, and thus to the electrical conductivity, in the section of the waveguides. This profile allows us to predict the DC drift of active components using the electro-optical effect. Moreover, coupled with confocal microscopy, this technique can give 2D and 3D maps of a waveguide at micro scale.