Nuclear electric field gradient determination for Fe2 ions in ferroelectric lithium niobate

Nuclear electric field gradient (EFG) parameters for Fe2+ ions in ferroelectric lithium niobate are determined using both single crystal orientation experiments and magnetic perturbation technique for polycrystalline samples. The results show clearly the presence of an axially symmetric EFG with no drastic change in the surrounding local environment. The different microscopic models, proposed to explain photorefractive processes in iron doped lithium niobate, are compared and critically reviewed with our experimental results.

Notes

Department of Physics, University of Poona, Poona, India

Fachbereich 6, Laboratorium fur Angewandte Physik, Gesamthochschule Duisburg, Duisburg, W. Germany