Linear optical properties and Raman spectroscopy of natural fluorapatite

Abstract

Precision refractive indices and their dispersion in the visible and near IR range (430 - 2400 nm) and thermal expansion (including its anisotropy and temperature dependence between 144 K and 673 K) were determined for gem-quality crystals of fluorapatite from Durango, Mexico. In addition, results of a polarized Raman spectroscopy study on these crystals are given. Fluorapatite crystals show moderate values of thermal expansion with small anisotropy. The linear optical properties of the crystals allow no phase matching for third harmonic generation, but signalize, together with the Raman characteristics, a potential suitability of fluorapatite as nonlinear optical material for chi((3))-based stimulated Raman scattering