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Magnetization curves for Pr2Fe14B single crystals were measured between 300 K and 900 K. The saturation magnetization Ms along the [1 0 0] direction was found to be 3% to 6% smaller than that for the [0 0 1] direction, not only at 300 K but also up to the Curie temperature. Published magnetization curves for Tm2Fe14B single crystals were reexamined, in which Ms along the [0 0 1] direction exceeds that for the [1 0 0] direction. We attributed these differences in Ms to the reduction of the rare-earth (R) moment when forced to be aligned along the hard direction by external fields. Significant anisotropy was observed in the paramagnetic susceptibility χ up to 900 K in the Pr2Fe14B (R = Pr) system. Based on the crystalline electric field parameters for R = Pr and Tm systems obtained by first-principles calculations, we numerically evaluated the magnetization and paramagnetic susceptibility at high temperatures. The differences in Ms and χ obtained from the calculation were in good agreement with the experiments. We found that the reduction rate for the Pr moment at the 4f site is much smaller than that at the 4 g site. This result suggests a crucial decrease in the local magnetic anisotropy at the Pr(4f) site.

The Nd-Fe-B/La thin films were deposited on the Al2O3(0001) substrate in order to investigate the effect of rare earth overlayer on the coercivity Hc. Highly textured Nd2Fe14B grains were grown by inserting the Mo(111) single crystal buffer layer. By depositing the La overlayer onto Nd2Fe14B thin films and subsequently post-annealing at 470 C, the Hc value increased from about 10.5 kOe to 15.0 kOe. The amount of Hc increase by the combination of the La coating and post-annealing was about 4.5 kOe. After the post annealing, La oxide (hcp La2O3) was formed in the La layer, which was confirmed by means of XRD and SIMS depth profile measurements.

Gilbert's damping constants, α , of Co( t Co )/Pt (1.4 nm) multilayer thin films are investigated by Q-band FMR analysis. α is calculated from the resonance width of the FMR spectrum. With decreasing t Co , the α value decreases from 0.034 ( t Co =8.7 nm) to 0.023 ( t Co =1.8 nm), and then increases to 0.037 ( t Co =1.0 nm). The decrease of α with t Co >1.8 nm is probably due to the eddy current loss effects. The increase of α with t Co θ =90° (parallel to the specimen) to θ =0° (perpendicular to the specimen), the α of all the specimens increased, and a sharp step in α was observed around θ =40°, where the α has the maximum value.

The inference of a magnetic field on the martensitic transformation (MT) temperatures and shape memory effect (SME) was investigated for the Ni-rich Ni 2 MnGa sputtered films. The compositions of the films were Ni 51.4 Mn 28.3 Ga 20.3 , Ni 54.1 Mn 23.0 Ga 22.9 and Ni 54.4 Mn 21.3 Ga 24.3 . The films were heat treated at 1073 K for 3.6 ks and aged at 673 K for 3.6 ks in a constrained condition. Hereafter, the constraint-aged films were described as N51.4(AG), N54.1(AG) and N54.4(AG) using nickel content, respectively. The reversible two-way SME by the thermal change was confirmed for the all constraint-aged films through the MT and its reversion. The gradient of the strain–temperature curve, the amount of strain accompanied by the two-way SME and the width of thermal hysteresis were dependent on the composition of the films. The strain–temperature curves shifted to a high temperature region and the martensitic phase was stabilized by the magnetic field. The strain at the outer surface was given by e = d /2 r , where d was the thickness of the films and r was the radius of a curvature for the films. The increase of MT temperatures caused by a magnetic field was about 1 K/T. Furthermore, the two-way SME by the magnetic field was observed around the MT temperature on cooling for the N54.4(AG) film with the large gradient and small thermal hysteresis in the strain–temperature curve.

Magnetoresistance (MR) of Ni–Mn–Ga–Fe shape memory films was investigated. The films with different Fe composition were prepared by co-sputtering method. The obtained films were heat-treated at 1073 K for 1 h in a flow of Ar gas. MR was measured by four point probe method at constant temperature by changing magnetic field up to ± 15 kOe . With increasing Fe composition, Curie temperature T c and saturation magnetization M s increased and martensitic transformation temperatures decreased. Negative and isotropic MR was found. MR at the magnetic field of 15 kOe increased with increasing temperature. MR of the film without Fe composition was - 0.44 % at 77 K and - 2.19 % at 353 K in martensitic phase. MR of the film containing 6.1 mol% Fe was - 0.30 % at 77 K in martensite phase and - 0.89 % at 353 K in austenitic phase. MR decreased with the increasing Fe composition. The MR of the films at R.T. below T c was larger than that at 77K. This temperature dependency of the MR suggest that negative MR of the constraint-aged Ni–Mn–Ga–Fe films is attributed to the s conduction electron scattering by the localized d spins in the modified s–d scattering model.

The electrical resistivity and magnetization as a function of temperature have been investigated for Cr 2 Se 3 and its Te-substitution system. The temperature dependence of electrical resistivity for Cr 2 Se 3 shows a metallic behavior above T N . That of Cr 2 Se 2.8 Te 0.2 shows a semiconductor-like behavior. The temperature dependence of magnetization of Cr 2 Se 2.8 Te 0.2 shows a canted antiferromagnet-like behavior.

Change in magnetization and electrical resistivity by annealing was examined for cold rolled Fe 47 Rh 53 alloy. The temperature hysteresis of magnetization was observed for the ferromagnetic phase. The resistivity increased with annealing time at 870 K. These results are discussed in relation to inhomogeneous magnetic and atomic structures.