METHOD OF MEASURING THE NONLINEAR REFRACTIVE INDEX COEFFICIENT OF A BISTABLE RESONANT CAVITY OPTICAL COMPONENT

摘要

In order to determine the nonlinear refractive index coefficient of a material which, when incorporated into a Fabry-Perot cavity has an optically bistable behaviour, the output power of the cavity is measured as a function of the power of an amplitude-modulated optical input signal in order to obtain a hysteresis loop characteristic of the material; the hysteresis loop saturation region is detected, in which the phase of the electromagnetic field associated with the signal within the cavity is a linear function of the output power; the values of the phase in that region are obtained from the output and input power values, and the nonlinear refractive index coefficient is obtained from the angular coefficient of the straight line representing the phase.