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Abstract: We epitaxially grew La0.5Ba0.5MnO3 (LBMO) films on (001)- and (111)-oriented ferroelectric single-crystal substrates and reduced the in-plane tensile strain of LBMO films by poling the ferroelectric substrates along the or direction. Upon poling, a large decrease in the resistance and a considerable increase in the magnetization, Curie temperature, and magnetoresistance were observed for the LBMO film, which are driven by interface strain coupling. Such strain effects can be significantly enhanced by the application of a magnetic field. An overall analysis of the findings reveals that the mutual interaction between the strain and the magnetic field is mediated by the electronic phase separation which is sensitive to both strain and magnetic field. Our findings highlight that the electronic phase separation is crucial in understanding the electric-field-manipulated strain effects in manganite film/ferroelectric crystal heterostructures. [Copyright &y& Elsevier]

Abstract: FeCoNd thin film with thickness of 166nm has been fabricated on silicon (111) substrates by magnetron co-sputtering and annealed for one hour under magnetic field at different temperatures (T a) from 200°C to 700°C. The As-deposited and annealed FeCoNd film samples at T a ≤500°C were amorphous while the ones obtained at T a ≥600°C were crystallized. We found that the perpendicular anisotropy field gradually decreases as the annealing temperature increases from room temperature to 300°C. A well induced in-plane uniaxial anisotropy is achieved at the annealing temperature between 400 and 600°C. The variation of the dynamic magnetic properties of annealed FeCoNd films can be well explained by the Landau–Lifshitz equation with the variation of the anisotropy field re-distribution and the damping constant upon magnetic annealing. The magnetic annealing might be a powerful post treatment method for high frequency application of magnetic thin films. [Copyright &y& Elsevier]

Abstract: In this Letter, bilayered Cu2O/CuO thin films were grown on Nb doped SrTiO3 (Nb:STO) substrates by plasma assisted molecular beam epitaxy. The current–voltage characteristics of Pt/Cu2O/CuO/Nb:STO devices show reproducible and pronounced current–voltage hysteresis which was induced by the CuO/Nb:STO junctions. By comparing the current–voltage curves of the bilayered and single-layered CuO thin films, we attribute the prominent switching behavior to the oxygen-vacancies-mediated-carriers-trapped-detrapped process with the aid of the applied forward (reversed) bias voltage. [Copyright &y& Elsevier]

Abstract: Smooth thin films of nickel(II), cobalt(II) and zinc(II) complexes with azo barbituric acid were prepared by the spin-coating method. Absorption spectra of the thin films on K9 glass substrates in 300–700nm wavelength region were measured. Optical constants (complex refractive index N = n +ik) of the thin films prepared on single-crystal silicon substrates in 275–695nm wavelength region were investigated on rotating analyzer–polarizer type of scanning ellipsometer, and dielectric constant ɛ (ɛ = ɛ 1 +iɛ 2) as well as absorption coefficient α of thin films were calculated at 405nm. In addition, static optical recording properties of the cobalt(II) complex thin film with an Ag reflective layer was carried out using a 406.7nm blue-violet laser and a high numerical aperture (NA) of 0.90. Clear recording marks with high reflectivity contrast (>60%) at proper laser power and pulse width were obtained, and the size of recording mark was as small as 250nm. The results indicate that these metal(II) complexes are promising organic recording medium for the blu-ray optical storage system. [Copyright &y& Elsevier]

Two nonequilibrium alloy phases were formed in the equilibrium immiscible Ni–Ru system by 200 keV xenon ion mixing of Ni–Ru multilayered films at 77 K, i.e. a metastable hcp phase near Ni75Ru25, and a metastable fcc phase with an alloy composition around Ni25Ru75. Interestingly, both the hcp and fcc phases were shown out simultaneously in the Ni50Ru50 multilayered films upon irradiation. A Gibbs-free energy diagram was constructed based on Miedema’s model and it can well explain the formation as well as the thermal stability of the above nonequilibrium phases. Based on a sliding mechanism, the lattice constants of the metastable phases were accordingly deduced and in good agreement with the experimentally determined values. Furthermore, the metastable hcp phase can be considered as a well-defined Hume-Rothery 7/4 electron compound. [Copyright &y& Elsevier]

We investigate the relationship between growth temperature and ferromagnetism in Mn:TiO2 thin film grown on SrTiO3:Nb substrate by plasma-assisted molecular beam epitaxy. The samples show different surface morphology, crystal quality and magnetic behavior with different growth temperature. It is concluded that the oxygen vacancies generated in the Mn:TiO2 thin film, together with the ones diffused from SrTiO3:Nb substrate, localize at the thin film/substrate interface during high-temperature growth, accounting for the more remarkable room-temperature ferromagnetism. [Copyright &y& Elsevier]

Au x /BaTiO 3 ( x = 0, 5, 10, 15, 25, 35, and 45, where x is mol% of Au) composite thin films dispersed by Au nanoparticles (NPs) were prepared by a sol–gel spin-coating approach. The crystal structure, optical and photocatalytic properties of the films were investigated with a special emphasis on the influences of x . The approximately spherical Au NPs with 20–45 nm in diameter are embedded uniformly in the amorphous BaTiO 3 matrix. The absorption peaks appeared at the wavelength from 580 to 620 nm are due to the surface plasmon resonance (SPR) effect of Au NPs, and the SPR peaks generally manifest a red-shift with increasing x from 5 to 45. The Au x /BaTiO 3 composite film with the optimal SPR effect ( x = 35) exhibits the highest photocatalytic activity for the degradation of Rhodamine B (RhB) aqueous solution among all films under whole spectrum sunlight irradiation. [ABSTRACT FROM AUTHOR]

Zn1−x Cd x O (x=0.2) thin films were deposited on glass substrates at different substrate temperatures (Ts) by the direct current (dc) reactive magnetron sputtering method. The influence of substrate temperature on structural and optical properties was investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), optical absorption spectra and Raman scattering in detail. Results indicated that all the obtained Zn1−x Cd x O (x=0.2) thin films were of highly (002)-preferred orientation and possessing the hexagonal wurtzite structure of pure ZnO, the crystalline quality first was improved and then deteriorated as the Ts increased up from 25°C to 600°C, when Ts is 550°C, the film had the best crystalline quality. Meanwhile, the optical band gap of Zn1−x Cd x O films was tuned from 2.728 to 2.782eV, which was attributed to the variation of the compressive stress and the Cd re-evaporation in the films. In addition, the residual stress and defects of films were evaluated from Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: A series of (Fe0.67Co0.33)1−xSmx (0≤x<0.25) thin films with thickness around 110nm have been fabricated on silicon(111) substrates by magnetron co-sputtering at ambient condition with a 2.4kA/m magnetic field applied in the film plane during deposition. With the Sm concentration increasing, FeCo grain size gradually decreases and FeCoSm film eventually becomes amorphous, while the isotropic magnetic property changes to in-plane uniaxial anisotropy as long as Sm is doped. The investigation of the angular dependence of coercivity and switching field indicates that the magnetization reversal mechanism of FeCoSm film is domain-wall depinning and coherent rotation when the applied field is close to the easy axis and hard axis, respectively. The anisotropy field and the resonance frequency of FeCoSm films can be tuned in the range of 15.0–109.5kA/m and 5.2–11.8GHz, respectively, by controlling the content of Sm, indicating that FeCoSm films have much potential in high-frequency applications. [Copyright &y& Elsevier]

Abstract: A method is developed to analyze the in-plane magnetic anisotropy from surface morphology for amorphous films. The lateral sizes along radial direction (R RD) and tangent direction (R TD) of rotational substrate, which are extracted from the surface morphology of Co66.3Zr33.7 amorphous films, are used to calculate stress anisotropy energy E σ. It is found that E σ is consistent with the magnetic anisotropy energy K μ for the samples deposited on Si (100) substrate and then a relationship K μ ∝1/R RD −1/R TD can be obtained. This method is sensitive to the initial state of substrate so its application range is discussed. [Copyright &y& Elsevier]

Abstract: HgCdTe thin films have been deposited on Si (111) substrates at different pressures by pulsed laser deposition (PLD). The HgCdTe thin films obtained at different pressures were characterized by X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDXA), scanning electron microscopy (SEM) and selected area electron diffraction (SAED). The results show that in our experimental conditions, the thickness, crystallinity, chemical content and surface morphology of the HgCdTe thin films have a strong relation to the change of pressure. The film obtained at 5×10−2 Pa has the highest crystal quality with the lowest Hg content. [Copyright &y& Elsevier]

Abstract: HgCdTe thin films have been deposited on Si(111) substrates at different substrate temperatures by pulsed laser deposition (PLD). An Nd:YAG pulsed laser with a wavelength of 1064nm was used as laser source. The influences of the substrate temperature on the crystalline quality, surface morphology and composition of HgCdTe thin films were characterized by X-ray diffraction (XRD), selected area electron diffraction (SAED), atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDS). The results show that in our experimental conditions, the HgCdTe thin films deposited at 200°C have the best quality. When the substrate temperature is over 250°C, the HgCdTe film becomes thermodynamically unstable and the quality of the film is degraded. [Copyright &y& Elsevier]

Abstract: The structure, thickness and adhesion to the substrate of the hard coatings used for protection against wear and corrosion are very important characteristics and they are strongly dependent on the internal stress induced into the coating during its growth. Development of a new class of coatings with a hardness of 2500–4500 HV0.1 and a thickness of 10–50 μm might increase significantly the application area of PVD coating in hydraulics, automotive, forming and even cutting tools. An ion assisted deposition method that combines magnetron sputtering and ion implantation (CMSII) as simultaneous processes has been used to produce nc-Ti2N/nc-TiN nanocomposite layers with such properties. In this paper, the cantilever method was used for in situ monitoring of the internal stress during the coating deposition. Generally, the internal stress produced by CMSII method is about half of that produced by magnetron sputtering without ion implantation. The structure of these coatings were analyzed by means of TEM. The adhesion and fracture properties of the coatings were analyzed by a mini version of a tensile test. [Copyright &y& Elsevier]