Various Types of Photoactive Behavior of the Y3Fe5O12 Ferrimagnetic Insulator

摘要

The photomagnetic behavior of single-crystal yttrium iron garnet Y_3Fe_5O_(12) doped with iridium, substituting the cation of iron in the octahedron, is investigated upon illumination at room temperature. It is shown that the photomagnetic properties of Y_3Fe_(4.97)Ir_(0.03)O_(12) samples are to a large degree related to the impurity distortion of the sublattice of iron atoms in octahedral coordination, rather than solely to the possible presence of Fe~(4+) cations, which are inactive at room temperature and may even be lacking in single crystals doped with iridium. It is concluded that the photoinduced change in the magnetic parameters of this material is determined by the location of impurity cations and increased surface imperfection of the material. The reasons for the different photoactive behavior of this promising material for spintronics, that is, a singlecrystal yttrium iron garnet, are summarized.