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We report a study on the interfacial antiferromagnetic coupling between ferrimagnetic TbIG/YIG thin films. TbIG/YIG bilayers are grown on YAG (110) substrates. The crystal structure and magnetic properties of the films are characterized. The temperature and directional dependences of the antiferromagnetic coupling effect are observed at low temperatures. This work enriches the magnetic research of ferrimagnetic oxide films with complex structures, providing new ideas for the design of antiferromagnetically coupled spintronics devices. [ABSTRACT FROM AUTHOR]

The Monte Carlo simulation has been used to investigate the magnetic properties of a mixed spin-1 (sublattice A) and spin-1/2 (sublattice B), where each sublattice has a rectangular structure and the whole lattice system forms a 2-D centered rectangular lattice. Five possible interactions are considered. Namely, two S–S interactions and two $\sigma $ – $\sigma $ interactions depend on crystal direction, and an antiferromagnetic interaction between the two sublattices is taken. Our results show that the critical temperature increases with increasing the variation of any exchange interactions. The existence of the compensation temperature depends on the balance between the S–S interactions along and $\sigma $ – $\sigma $ interactions along [01] directions. [ABSTRACT FROM AUTHOR]

Millimeter wave (MMW) absorption measurements have been conducted on commercial samples of large (micrometer-sized) and small (nanometer-sized) particles of BaFe12O19 and SrFe12O19 using a quasi-optical MMW spectrometer and a series of backwards wave oscillators encompassing the 30–120 GHz range. Effective anisotropy of the particles calculated from the resonant absorption frequency indicates lower overall anisotropy in the nano-particles. Due to their high magnetocrystalline anisotropy, both BaFe12O19 and SrFe12O19 are expected to have spin resonances in the 45–55 GHz range. Several of the sampled BaFe12O19 powders did not have MMW absorptions, so they were further investigated by DC magnetization and x-ray diffraction to assess magnetic behavior and structure. The samples with absent MMW absorption contained primarily iron oxides, suggesting that MMW absorption could be used for quality control in hexaferrite powder manufacture. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the layer thickness and the surface intralayer exchange coupling on the magnetic and thermodynamic properties of the mixed spin-2 and spin-5/2 ferrimagnetic systems are studied in detail by the Monte Carlo simulation. A number of interesting phenomena have been found. The results show that there exist the significant dependences of the compensation temperature, phase transition temperature, and the hysteresis loop of the system on both layer thickness and surface intralayer exchange coupling. [ABSTRACT FROM AUTHOR]

The effects of deposition order on the magnetic properties of the NiFe/NiMn exchange couple were studied. The use of a thin underlayer, to enhance these properties, was also investigated for the deposition order NiMn/NiFe. We found that the use of such an underlayer was essential for the exchange field to be greater than the coercivity. We observed that the underlayer film thickness did not have a dramatic effect on the final exchange field obtained. X-ray diffraction studies did not reveal a strong correlation between film texture and exchange fields. The blocking temperature was also measured for the deposition order NiFe/NiMn. [ABSTRACT FROM PUBLISHER]