Optical properties of Nd~(3+)-doped Ca_3(VO_4)_2 single crystal fiber

摘要

Optical absorption and photoluminescence of Ca_3(VO_4)_2 single crystal grown by a floating-zone technique and containing Nd~(3+) ions were investigated. High absorption coefficients and broadening of most absorption bands are present at 300 K, while substructures in some of the same bands can be evidenced at 12 K. Most features of measured spectra are characteristic of random occupation of more than a single Ca~(2+) site by the Nd~(3+) ion and of distortions provoked by different charge compensation mechanisms involving oxygen vacancies promotion in the crystal lattice. Nd~(3+) optical properties were studied by using the Judd-Ofelt theory to calculate the spectral parameters relevant for laser applications.