EPR study of Er3+ in congruent LiNbO3

Erbium doped congruent LiNbO3 has been investigated with electron paramagnetic resonance (EPR). For the orientation of the magnetic field parallel to the c-axis the previously observed characteristic hyperfine split EPR spectrum of Er3+ was measured. However, the angular dependence shows line splittings not reported before. They can be attributed to Er3+ defects on Lit sites next to Li+ vacancies (V-Li(+)), which tilt the g-tensor orientation away from the c-axis. Several differently oriented Er3+-V-Li(+) complexes have been identified. The EPR spectrum can be explained;assuming a statistical distribution of Vh in the neighborhood of Er3+-V-Li(+). (C) 1997 Published by Elsevier Science Ltd.