Anomalies in the magnetic properties of bismuth-substituted diluted yttrium iron garnet

Aplesnin, S.S., Zelenov, F.V., Semenov, S.V., Bayukov, O.A.// Journal of Magnetism and Magnetic Materials//

The magnetic properties and Mössbauer spectra of the Y1.8Bi1.2Fe3.5Ga1.5O12 compound were investigated. A linear temperature dependence of the saturation magnetization, hysteresis, and stability of the coercive field in the magnetically ordered state were found. Using the Mössbauer measurements, the distribution of iron ions over octahedral and tetrahedral sites and the concentration of paramagnetic iron ions were determined. Two critical temperatures – the sublattice magnetization compensation temperature and the ferrimagnet–paramagnet transition temperature – were established. The disappear of the phonon mode in the vicinity of the magnetic transition was observed. The experimental data have been interpreted in terms of the spin–lattice interaction model.