Magnetization process and site preference of Bi in YIG: Bi epitaxial films studied by 57Fe NMR

The NMR of 57 Fe was used to determine the distribution of Bi 3+ ions on the dodechedral sublattice of thin YIG: Bi films with (111) orientation. In a film with 11% Bi 3+ on Y sites the two sublattices which are non-equivalent with respect to the growth direction reveal a difference in the Bi concentration of 10%. The growth induced anisotropy constant was determined from the FMR spectra and allows an estimation of the change of the second order crystal field parameters for the Fe 3+ neighbors of a Bi 3+ ion.