Optical spectroscopy of SrWO4:Nd3+ single crystals

The optical properties of SrWO4 crystals doped with Nd3+ have been investigated at temperatures ranging from 10 to 300 K. The scheme of the energy levels up to 20 000 cm(-1) has been deduced from low temperature measurements and reproduced by theoretical calculations based on a parametric Hamiltonian including Coulombic, spin-orbit and crystal field terms. The spontaneous transition probabilities, the branching ratios and the radiative lifetime have been calculated in the framework of the Judd-Ofelt theory and compared with the experimental results for the F-4(3/2) emitting level. The optical bands are broadened because of crystal field inhomogeneities caused by charge compensation processes accompanying the substitution of Nd3+ for Sr2+. This fact and the high emission cross section values obtained for the emission from the F-4(3/2) multiplet indicate Nd:SrWO4 as a possible. active medium for tunable laser operation.