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The angular dependence of the microwave-driven spin rectification (SR) effect in single crystalline Co _0.5 Fe _0.5 alloy film is systematically investigated. Due to the strong current-orientation dependent anisotropic magnetoresistance (AMR), the SR effects in CoFe film strongly deviate from the ordinary sin 2 φ _M cos φ _M relation with φ _M defined as the magnetization angle away from the current. A giant Gilbert damping anisotropy in the CoFe film with a maximum–minimum ratio of 520% is observed, which can impose a strong anisotropy onto magnetic susceptibility. The observed unusual angular dependence can be well explained by the theory including current-orientation dependent AMR and anisotropic magnetic susceptibility. Our work also suggests that the strong current-orientation dependent AMR in single crystalline CoFe film could exist up to the gigahertz frequency range.

LaCoO3 epitaxial films were grown on (100), (110) and (111) oriented LaAlO3 substrates by the polymer-assisted deposition method. Crystal structure measurement and cross-section observation indicate that all the LaCoO3 films are epitaxially grown in accordance with the orientation of LaAlO3 substrates, with biaxial compressive strain in the ab plane. Owing to the different strain directions of CoO6 octahedron, the mean Co–O bond length increases by different amounts in (100), (110) and (111) oriented films compared with that of bulk LaCoO3, and the (100) oriented LaCoO3 has the largest increase. Photocatalytic degradation of methyl orange indicates that the order of photocatalytic activity of the three oriented films is (100) > (111) > (110). Combined with analysis of electronic nature and band structure for LaCoO3 films, it is found that the change of the photocatalytic activity is closely related to the crystal field splitting energy of Co3+ and Co–O binding energy. The increase in the mean Co–O bond length will decrease the crystal field splitting energy of Co3+ and Co–O binding energy and further reduce the value of band gap energy, thus improving the photocatalytic activity. This may also provide a clue for expanding the visible-light-induced photocatalytic application of LaCoO3.

Mn\(_3\)Ge has a tetragonal Heusler-like D0\(_{22}\) crystal structure, exhibiting a large uniaxial magnetic anisotropy and small saturation magnetization due to its ferrimagnetic spin structure; thus, it is a hard ferrimagnet. In this report, epitaxial growth of a Mn\(_3\)Ge film on a Rh buffer layer was investigated for comparison with that of a film on a Cr buffer layer in terms of the lattice mismatch between Mn\(_3\)Ge and the buffer layer. The film grown on Rh had much better crystalline quality than that grown on Cr, which can be attributed to the small lattice mismatch. Epitaxial films of Mn\(_3\)Ge on Rh show somewhat small coercivity (\(H_{\rm c}\) = 12.6 kOe) and a large perpendicular magnetic anisotropy (\(K_{\rm u}\) = 11.6 Merg/cm\(^3\)), comparable to that of the film grown on Cr.

Abstract We report on the analysis of weak localization observed in epitaxial films of LaNiO 3-δ deposited coherently on SrTiO 3 (001) substrates using different oxygen pressures, controlling thus the oxygen stoichiometry δ. The structural and transport properties of 10 nm thick LaNiO 3-δ films were investigated. In the films deposited under the lowest oxygen pressures, we observe localization effects at low temperatures, indicating first a high structural quality of the films, and second an influence of the growth conditions on the quantum transport properties of the nickelate. We will discuss the origin as well as the dimensionality of this effect, giving insight into novel and accurate strategies for the design of ultrathin LaNiO 3 electrodes for improved next generation electronics devices. Highlights • The significant effect of oxygen pressure during epitaxial film growth is studied. • The structural, electrical properties and film growth conditions are investigated. • The films deposited at low oxygen pressure exhibits weak localization. • The quantum transport in the nickelate films and their film growth are discussed. [ABSTRACT FROM AUTHOR]

Magnetoelectric properties of ferrite garnets are of great interest due to possibility of electric control of micromagnetic structures at room temperatures promising for applications in advanced technologies. However, the governing mechanisms underlying magnetoelectric coupling and origin of ferroelectricity in these materials remain under discussion. In this article, we appeal to polar mechanism related to electric dipole moments of Fe 3+ and rare earth ions in order to explain ferroelectricity of epitaxial ferrite garnet film. We show that existence of electric dipole moments of ‘ d ’ (Fe 3+ ) ions and ‘ f ’ (rare earth) ions is allowed by the local symmetry of the environments and calculate electric polarization related to electric dipole moments of the ‘ d ’ and the ‘ f ’ ions in inhomogeneously magnetized ferrite garnet film. Our results suggest that magnetoelectricity of iron garnets is attributed to polarizability of Fe 3+ and rare earth ions; the conducted calculations demonstrate the difference between polarization impacts given by electric dipole moments of rare earth and iron ions. Polarization depend on ground state of the ions, local symmetry of the ions environments and the type of magnetic inhomogeneity. [ABSTRACT FROM AUTHOR]

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We have investigated the energy transfers in the 1.54- μ m region of (Er,Sc) 2 O 3 epitaxial thin films grown on Si(111). The interplay of the energy transfers between Er ions in the different and the same symmetry sites makes the dynamics complicated. To suppress the energy transfer upconversion, low power and resonant excitation of the third crystal-field level ( 4 I 13 / 2 : Y 3 ′ ) of the Er 3 + site with C 3 i symmetry was employed. The time-resolved photoluminescence measurements of the Y 1 ′ - Z 1 ′ transition indicate the existence of two decay components having fast (10–100 μ s) and slow (0.1–1 ms) relaxation times in the range of 4–60 K. The model calculation including the inter-site energy transfers, the temperature-sensitive and -insensitive non-radiative relaxations fits the experimental results well. Moreover, the long averaged inter-Er 3 + distance obtained by decreasing Er concentration was found to reduce two kinds of non-radiative relaxation rates and the energy transfer rates between Er ions very effectively. [ABSTRACT FROM AUTHOR]

Transport properties were investigated for epitaxial films of superconductor NbN and half-metallic Heusler alloy Co 2 MnSi under high magnetic fields up to 17 T. The superconducting transition temperature T c of NbN/Co 2 MnSi/Au trilayer films was determined to be 16.1 K in the absence of magnetic field. Temperature dependence of the resistivity ρ ( T ) was measured in both magnetic fields parallel and perpendicular to the surface of NbN/Co 2 MnSi/Au trilayer films. The activation energy U 0 ( H ) for vortex motion of the trilayer films in both magnetic fields was well fitted above 5 T by the similar model with the exponents in the field dependence of the pinning force density. From the resistivity ρ ( T ) measurements under high magnetic fields, the upper critical field H c 2 ( 0 ) at 0 K was also deduced to be μ 0 H c 2 ∥ ( 0 ) = 23.2 T for the parallel magnetic filed and μ 0 H c 2 ⊥ ( 0 ) = 15.8 T for the perpendicular magnetic field, respectively. The experimental results under magnetic fields revealed the superconductivity of the NbN layer was affected by the interplay between the superconducting NbN layer and the half-metallic Co 2 MnSi layer. [ABSTRACT FROM AUTHOR]

Morphology of single Shockley-type stacking faults (SFs) generated by recombination enhanced dislocation glide (REDG) in 4H–SiC are discussed and analysed. A complete set of the 12 different dissociated states of basal-plane dislocation loops is obtained using the crystallographic space group operations. From this set, six different double rhombic-shaped SFs are derived. These tables indicate the rules that connect shapes of SFs with the locations of partial dislocations having different core structures, the positions of slip planes in a unit cell, and the Burgers vectors of partial dislocations. We applied these tables for the analysis of SFs generated by the REDG effect reported in the past articles. Shapes, growing process of SFs and perfect dislocations for origins of SFs were well analysed systematically. [ABSTRACT FROM AUTHOR]

Inclined epitaxial La 1−x Ca x MnO 3 films based on the light-induced transverse thermoelectric (LITT) effect have attracted significant attention in fast light/thermal detection. In this work, a series of inclined La 1−x Ca x MnO 3 (0.1≤x≤0.8) films are fabricated based on a home-designed MOCVD system by adjusting the ratio of La/Ca sources. The composition-induced microstructure for La 1−x Ca x MnO 3 films is revealed. La 1−x Ca x MnO 3 tends to form a single orientation under a small lattice mismatch with the substrate, while with a multi-domain structure under an obvious mismatch, significant lattice distortions are observed in the films. With increasing Ca content, the electrical conductivity gradually increases, which is responsible for enhanced response voltage from 5.5 V for Ca10 to 25.5 V for Ca40. However, with a further increase in conductivity, the response voltage gradually decreases, which may be attributed to the deteriorated anisotropic Seebeck coefficient. Benefitting from enhanced conductivity, the response time decreases from 2984 ns for Ca10 to 58 ns for Ca60, which increases to 80 ns for Ca80 due to enhanced phonon scattering originating from the lattice distortions. This work may serve as a reference for modulating the LITT effect based on electron/phonon transport for other material systems applied in fast light/thermal detection. [Display omitted] • Inclined La 1−x Ca x MnO 3 (0.1≤x≤0.8) with good biaxial texture are prepared by MOCVD. • Composition-induced microstructure is revealed for La 1−x Ca x MnO 3 films. • Increased conductivity conduces to enhance LITT voltage and reduce response time. • Enhanced phonon scattering from lattice distortions prolongs the response time. [ABSTRACT FROM AUTHOR]

This paper reports the structure transformation of Ti films deposited on SiC(0001) single crystal substrates using DC magnetron sputtering. Film thickness, sputter power and temperature of deposition were changed to investigate structure transformation of Ti films. The structure characterization of Ti film was performed by means of X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscope (HRTEM). The results showed that the Ti film grew epitaxially with a face centered cubic ( fcc ) structure even the thickness is up to about 50 nm. High temperature and low sputter power are propitious to the formation of fcc -Ti. An interesting intermediate state of the fcc-hcp transformation was observed. This intermediate structure could help us to understand the mechanism of thickness-dependent fcc-hcp transformation in Ti thin films. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the photocatalytic performance, heterogeneous elements have been doped in the lattice of photocatalyts, but the lattice distortion induced by the doping has not been sufficiently discussed. We now demonstrate the effect of the lattice distortion of TiO on its photocatalytic performance. A lattice-distorted TiO film showed a significantly higher photocatalytic activity than a non-distorted TiO film. For the lattice-distorted TiO film, a gradient of the lattice parameter was formed, leading to the forming of potential slopes of the valence band maximum and conduction band minimum as confirmed by DFT calculations. The potential slopes promote effective separation of the electron-hole to improve the photocatalytic performance. Graphical Abstract: [ABSTRACT FROM AUTHOR]

We report structural, magnetic, and transport properties of epitaxial films of superconductor NbN and highly spin-polarized Heusler alloy Co2Fe0.4Mn0.6Si (CFMS). The saturation magnetization Ms of the film was 870 emu/cm3, which is slightly smaller than values reported earlier. With an increase of CFMS thickness dCFMS, the sheet resistance Rsq decreased and the upper critical field μ0Hc2(0) decreased monotonically, while the superconducting transition temperature Tc exhibited a minimum around dCFMS = 3 nm. A theoretical analysis of superconducting fluctuations revealed that the high spin polarization of the CFMS layer affected the pair breaking parameter δ, the superconducting coherence length ξ(0), and the diffusion coefficient D. [ABSTRACT FROM PUBLISHER]

The optimal conditions (υк = 8−9 Å/s; Тп = 673 K) to obtain structurally perfect (W1/2 = 100″−140″) Cd1 − x(Mn, Fe)xSe epitaxial films in the (111) plane are determined. The structure and surface morphology of the epitaxial films are studied. It is established that in Cd1 − x(Mn, Fe)xSe thin films, unlike bulk samples, the sphalerite structure with the lattice parameter a = 6.05 Å is formed. Using an additional source of Se vapor during growth, Cd1 − x(Mn, Fe)xSe epitaxial films with a clean, smooth surface are obtained. [ABSTRACT FROM AUTHOR]