Measurements of the electronic and nuclear contributions to the nonlinear refractive index of beryllium fluoride glasses

摘要

The nonlinear refractive‐index coefficientn2of three beryllium fluoride glasses was measured at 1064 nm using time‐resolved interferometry. The refractive‐index nonlinearity of amorphous BeF2is the smallest reported for any solid. From Raman scattering spectra, the nuclear contributionn2was found to be ≈20–30% of the total, a factor similar to that for oxide glasses.