An analysis of the high resolution optical spectra (10 and 300 K) of the self-stimulated
Raman scattering active Nd: SrWO 4 crystal was performed. Crystals doped only with low
concentrations of Nd or codoped with Na+ or Nb 5+ grown in N 2 or air atmosphere were
investigated. The single Nd-doped crystals show five main centers, whereas codoping with
Na+ in the ratio Na/Nd= 3/1 (in melt) simplifies considerably the spectra. Codoping with Nb
5+ does not lead to a dominant center and introduces a new one. Growth in air revealed the …