Nonlinear characterization of waveguide index profile: application to soft-proton-exchange in LiNbO3

In integrated photonics, the precise knowledge of the waveguides refractive index profile is mandatory for the modeling of photonic chips and therefore implementing innovative circuits. Usual index profile determination relies on effective index measurement of propagating modes in planar waveguides coupled with numerical fitting tools. In this paper we propose an alternative technique based on the...