Three-color nonlinear optical mixing for the determination of the refractive index dispersion of a tellurite glass

We determine the refractive index dispersion of a quaternary tungsten-tellurite glass over a broad spectral range from 0.4 to 3 mu m from the wavelength dependence of the phase matching conditions for third-order nonlinear optical frequency conversion. We discuss the optimum phase-matching geometries for this task and obtain the wavelength-dependence of the refractive index to within three significant digits by a least-squares fit of a Sellmeier-type equation to the phase-matching data. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3492850]