No abstract

Bi2.5Y0.5Fe5O12 and Bi3Fe5O12 thin films were prepared on Gd3Ga5O12 substrates using a metal organic decomposition (MOD) method as magneto-optical indicators (MOI) to visualize the distribution of magnetic flux. Their structural and magneto-optical properties were studied. The Faraday rotations of Bi2.5Y0.5Fe5O12 and Bi3Fe5O12 thin films were 15.5 m/degrees at a wavelength of 524 nm for the former and 23.0 m/degrees at 530 nm for the latter. We found that these films prepared by MOD were suitable for MOI, because of their large Faraday rotation, in-plane magnetic anisotropy, and extinct magnetic domain structures.

No abstract

GdFe spin-valve structures, Si/bottom electrode/TbFeCo/CoFe (1 nm)/Cu (6 nm)/GdFe (10 nm)/Ru, with dimensions of 20×20 μm2 were investigated by a magneto-optical imaging technique. In a parallel configuration, i.e., a configuration in which the magnetization directions of GdFe and TbFeCo layers are parallel, the coercivity (Hc) decreases when nucleation centers are present in the patterns. In the antiparallel configuration, although few nucleation centers are present the deviation in Hc is greater than that in the parallel configuration.

The MO spectra of GMR structures with capping layers, Si/SiO2/bottom electrode/TbFeCo (9 nm)/Cu (4 nm)/ Co (0.1 nm)/Pt (1.1 nm)/(Pt (1.1 nm)/Co (6 nm)!4)/cap (cap = Ta, Au, Pt (3 nm)), were studied. We found that the optical constants and Kerr spectra exhibited different behaviors for all samples. The differences in the optical constants of these samples were analyzed by means of optical simulation. The MO spectrum is discussed in terms of simulation carried out by the virtual optical constant method for (PtCo)/cap (cap = Ta, Au, Pt (3 nm)).