Electron paramagnetic resonance experiments were performed on congruent crystals which were heavily doped with Mg or Zn, and were co-doped with Er. A new Er spectrum was detected in samples which were co-doped with Mg or Zn. The new spectrum had g-values of g|| = 4.3 and g = 7.6 for Mg-doped samples and g|| = 4.26 and g = 7.8 for Zn-doped samples. The spectrum was associated with a new Er3+ centre, and was concluded to be due to Er3+ which was located at the Nb5+ site.

A New EPR Centre of Er3+ in MgO or ZnO Co-Doped LiNbO3 Single Crystals. D.Bravo, A.Martín, F.J.López: Solid State Communications, 1999, 112[10], 541-4