Photomagnetic effects in single-crystal Ru-doped lithium ferrite

Anisotropy and magnetostriction of ruthenium-substituted lithium ferrite and nickel ferrite

“…Saturation magnetization measurements on polycrystalline ruthenium-doped lithium ferrites have been reported by Jonker [23], who concluded that the ruthenium ions are present in the low-spin state on octahedral sites in accordance with EPIt measurements on other materials [32 to 341. From the magnetization measurements, however, no prediction could be made about their valence state.…”

“…I n this case the change was attributed to an increasing tetrahedral occupation. But no change in the site preference is expected [40] in these spinel ferrites since in all oxydic compounds ruthenium was found to occupy octahedral sites [23]. However, in the case of octahedral ruthenium ions the anisotropy contributions observed cannot be explained in terms of the single-ion model neither for R u~+ nor for Ru4+ if a level structure is assumed such as is used to describe the ferromagnetic resonance effects in garnets or the EPR results.…”

Photo-induced bias of the hysteresis loop in ferrites at room temperature with long-time memory

“…For garnet [1], ferrite [13,14], and magnetic semiconductor [15] materials, a white light illumination at low (77 K) temperature increased the loop squarness and coercivity.…”