Here, we report the realization of epitaxial Y3Fe5O12 (YIG) thin films with perpendicular magnetic anisotropy (PMA). The films are grown on the substituted gadolinium gallium garnet substrate (SGGG) by pulsed laser deposition. It was found that a thin buffer layer of Sm3Ga5O12 (SmGG) grown on top of SGGG can suppress the strain relaxation, which helps induce a large enough PMA to overcome the shape anisotropy in YIG thin films. The reciprocal space mappings analysis reveals that the in-plane strain relaxation is suppressed, while the out-of-plane strain relaxation exhibits a strong dependence on the film thickness. We found that the PMA can be achieved for both bilayer (YIG/SmGG) and tri-layer (SmGG/YIG/SmGG) structural films with YIG layer thicknesses up to 20 nm and 40 nm, respectively.

By suppressing the growth of impurities, a melt spinning method was successfully applied to the synthesis of typical 1 : 2 : 2 layered CeMn 2 Si 2 and AlFe 2 B 2 compounds. X-ray diffraction analysis showed that CeMn 2 Si 2 and AlFe 2 B 2 had good purity and crystallized in ThCr 2 Si 2 -and AlFe 2 B 2 -type structures, respectively. The differences among three 1 : 2 : 2-type structures were also analyzed. The magnetic properties were investigated by magnetic measurements and electronic structure calculations. It was found that the Fe moment of AlFe 2 B 2 reaches 1.32 μ B at 5 K, which fits well with the calculated result of 1.44 μ B at 0 K, and that the isothermal magnetic entropy change reaches 7.2 J kg %1 K %1 at 5 T, which shows great potential for room-temperature refrigeration applications.

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Stability is an important issue for the application of resistive switching (RS) devices. In this work, the endurance and retention properties of Ag/CoOx/Ag interface-type RS device were investigated. This device exhibits rectifying I–V curve, multilevel storage states and retention decay behavior, which are all related to the Schottky barrier at the interface. The device can switch for thousands of cycles without endurance failure and shows narrow resistance distributions with relatively low fluctuation. However, both the high and low resistance states spontaneously decay to an intermediate resistance state during the retention test. This retention decay phenomenon is due to the short lifetime τ (τ = 0.5 s) of the metastable pinning effect caused by the interface states. The data analysis indicated that the pinning effect is dependent on the depth and density of the interface state energy levels, which determine the retention stability and the switching ratio, respectively. This suggests that an appropriate interface structure can improve the stability of the interface-type RS device

The structure and magnetic properties of MnCoSi1− x Px (x = 0.05–0.50) are systematically investigated. With P content increasing, the lattice parameter a increases monotonically while both b and c decrease. At the same time, the temperature of metamagnetic transition from a low-temperature non-collinear ferromagnetic state to a high-temperature ferromagnetic state decreases and a new magnetic transition from a higher-magnetization ferromagnetic state to a lower-magnetization ferromagnetic state is observed in each of these compounds for the first time. This is explained by the changes of crystal structure and distance between Mn and Si atoms with the increase of temperature according to the high-temperature XRD result. The metamagnetic transition is found to be a second-order magnetic transition accompanied by a low inversed magnetocaloric effect (1.0 J·kg−1·K−1 at 5 T) with a large temperature span (190 K at 5 T) compared with the scenario of MnCoSi. The changes in the order of metamagnetic transition and structure make P-doped MoCoSi compounds good candidates for the study of magnetoelastic coupling and the modulation of magnetic phase transition.