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The spin mixing conductance g↑↓ of a ferromagnetic and a nonmagnetic (NM) layer characterizes the transport efficiency of spin current through the interface. Exploration of the relationship between g↑↓ and structural parameters such as the lattice orientation of the NM layer is critical to design effective spintronics devices. Here, the spin mixing conductance of two types of single oriented Pt and Ni81Fe19 (Py) was studied experimentally, with the method of spin pumping. The obtained g↑↓ for Pt (100)/Py and Pt (111)/Py bilayers is 8.6 ± 0.9 nm−2 and 10.8 ± 1.6 nm−2, respectively, revealing the fact that the crystalline orientation of the metallic NM layer has no prominent impact on g↑↓, which is consistent with the theoretical prediction.

The perpendicular magnetic anisotropy (PMA) and perpendicular exchange bias (PEB) have been investigated in a CoPt/spacer/FeMn heterostructure by inserting Ta and Pt as spacer layers, respectively. First, we show that strong PMA can be obtained in (111)-oriented A1-CoPt single layer and CoPt/FeMn bilayer films on MgO (111) substrates. Then we demonstrate that the Ta and Pt spacer layers have largely different effects on the PMA and PEB of the CoPt/spacer/FeMn films. By increasing the thickness of the Ta spacer layer to 1 nm, the PMA and PEB drastically decrease. While, in the case of Pt, the PMA and PEB increase first, then slightly decrease. When the Pt spacer layer is 1 nm, a value of 85 Oe of the long-range PEB still can be obtained. The possible mechanisms were discussed to explain the different trends of PMA and PEB. Since Ta and Pt are the generally used materials in the spintronics, our study provides a piece of information for the control of the magnetic anisotropy and exchange bias in the current-induced magnetization switching of ferromagnet without external magnetic field.

The hydrogen absorption/desorption processes of (111)-textured and normal palladium (Pd) thin films of thickness ranging from 8 to 48 nm are investigated using X-ray diffractometry. The one-dimensional expansion of Pd lattice due to the substrate clamping is observed at the low hydrogen composition phase while both out-of-plane and in-plane expansions are detected at the high hydrogen composition phase. Accordingly, using a biaxial Poisson’s ratio, an anisotropic expansion factor is proposed for describing such phenomenon quantitatively and the hydrogen composition dependence on this factor is investigated.

BiFeO3/TiN/MgO (001) films have been prepared by magneton sputtering, where TiN serves as a conductive under layer. X-ray diffraction profiles and cross-sectional transmission electron microscopy images reveal that not only (001)-epitaxial BiFeO3 films are obtained, but also both tetragonal and rhombohedral phases co-exist in BiFeO3 films. Their crystallographic relationship is shown as following: tetragonal-BiFeO3 (001) [100]//TiN (001) [100]//MgO (001) [100] and rhombohedral-BiFeO3 (001) [100]//TiN (001) [100]//MgO (001) [100]. Besides, an oxidized TiN layer (∼ 20 nm) has also been detected between BiFeO3 and TiN layers and its formation may originate from oxygen inter-diffusion from BiFeO3 layer. Despite of the existence of the oxidized TiN layer, it does not affect the epitaxial growth of BiFeO3 films. On the other hand, the coercivity electric field obtained in ferroelectric loop of BiFeO3 is greatly enhanced to 49 MV/cm due to the existence of oxidized TiN layer.

The CuxSi1−x thin films have been successfully fabricated by pulsed laser deposition (PLD). The influences of laser energy fluency (I0) and deposition temperature (Td) on the phase structure were investigated. The results show that Cu deposited on Si (001) at I0 = 0.5-2.0 J/cm2, and η”-Cu3Si formed on Si (111) at I0 = 1.0-2.0 J/cm2. The films were consisted of Cu, η’-Cu3Si, ε-Cu15Si4 and δ-Cu0.83Si0.17 at Td = 100-500 °C on Si (001). The films were the single phase of η-Cu3Si at Td = 700 °C. In the case of Si (111), the phase structures transformed from Cu to Cu + η’-Cu3Si to η’-Cu3Si to η’-Cu3Si + η-Cu3Si with the increasing of Td. Rectangular grains were formed on Si (001), whereas triangular grains on Si (111). Cu (001) film was epitaxially grown on Si (001) at I0 = 1.5 J/cm2 and Td = 20 °C. η-Cu3Si (001) epitaxial layer was formed on Si (111) at I0 = 1.5 J/cm2 and Td = 700 °C. The epitaxial relationships of Cu (001)[100]//Si (001)[110] and η-Cu3Si (001)[-110]//Si (111)[11-2] were identified.

BiFeO3/TiN/MgO (001) films have been prepared by magneton sputtering, where TiN serves as a conductive under layer. X-ray diffraction profiles and cross-sectional transmission electron microscopy images reveal that not only (001)-epitaxial BiFeO3 films are obtained, but also both tetragonal and rhombohedral phases co-exist in BiFeO3 films. Their crystallographic relationship is shown as following: tetragonal- BiFeO3 (001) [100]//TiN (001) [100]//MgO (001) [100] and rhombohedral-BiFeO3 (001) [100]//TiN (001) [100]//MgO (001) [100]. Besides, an oxidized TiN layer (~ 20 nm) has also been detected between BiFeO3 and TiN layers and its formation may originate from oxygen inter-diffusion from BiFeO3 layer. Despite of the existence of the oxidized TiN layer, it does not affect the epitaxial growth of BiFeO3 films. On the other hand, the coercivity electric field obtained in ferroelectric loop of BiFeO3 is greatly enhanced to 49 MV/cm due to the existence of oxidized TiN layer. [ABSTRACT FROM AUTHOR]

The CuxSi1-x thin films have been successfully fabricated by pulsed laser deposition (PLD). The influences of laser energy fluency (I0) and deposition temperature (Td) on the phase structure were investigated. The results show that Cu deposited on Si (001) at I0 = 0.5-2.0 J/cm², and η"-Cu3Si formed on Si (111) at I0 = 1.0-2.0 J/cm². The films were consisted of Cu, η'-Cu3Si, ε-Cu15Si4 and δ-Cu0.83Si0.17 at Td = 100-500 °C on Si (001). The films were the single phase of η-Cu3Si at Td = 700 °C. In the case of Si (111), the phase structures transformed from Cu to Cu + η'-Cu3Si to η'-Cu3Si to η'-Cu3Si + η-Cu3Si with the increasing of Td. Rectangular grains were formed on Si (001), whereas triangular grains on Si (111). Cu (001) film was epitaxially grown on Si (001) at I0 = 1.5 J/cm² and Td = 20 °C. n-Cu3Si (001) epitaxial layer was formed on Si (111) at I0 = 1.5 J/cm² and Td = 700 °C. The epitaxial relationships of Cu (001)[100]//Si (001)[110] and η-Cu3Si (001)[-110]//Si (111)[11-2] were identified. [ABSTRACT FROM AUTHOR]