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Highlights: [•] Introduction of oxygen vacancy in NaNbO3 sub-micron cube through the thermal annealing with Zr foil in vacuum. [•] Confirmation of the Pmc21symmetry for oxygen-deficient NaNbO3−δ . [•] Observation of coexistence of piezoelectricity and electric conduction in oxygen-deficient NaNbO3−δ sub-micron cubes. [Copyright &y& Elsevier]

Highlights: [•] Synthesis of BaTiO3/ZnFe2O4 core/shell nanoparticles. [•] Nanoparticles are ferromagnetic with spontaneous magnetization of 8emu/g. [•] Dielectric constant is found to increase with temperature. [•] About 1.3% change, in dielectric constant at 1T of magnetic field. [ABSTRACT FROM AUTHOR]

Abstract: The temperature variations of the elastic constant C 11 and the corresponding acoustic attenuation coefficient of barium titanate single crystals grown by two different methods in the paraelectric phase were obtained in a wide temperature by means of Brillouin light scattering. Two phenomenological approaches were adopted to attempt to explain the anomalous change in C 11 (denoted as ΔC 11) in the paraelectric phase. ΔC 11 exhibited a logarithmic variation as log[(T − T 0)/T 0] in a certain temperature range from T c to about T c +80°C instead of the other variation of (T − T 0) ζ predicted by the mean-field approach. This temperature range was almost the same as the range where precursor dynamics were theoretically predicted to set in. The fact that the logarithmic variation was proposed for uniaxial systems might indicate that the correlated deformation of precursor polar clusters is tetragonal, as was suggested from nuclear magnetic resonance study . [Copyright &y& Elsevier]

Abstract: We report the structural and photoluminescence characteristics of a high energy Ar+-irradiated SrTiO3 single crystal. High resolution X-ray reciprocal space mapping, cross-section scanning electron microscopy and photoluminescence measurements suggest that thick amorphous and oxygen-deficient SrTiO3 layers are formed after irradiation. Due to the highly accelerated Ar+ (∼100keV), electrical conductivity of the oxygen-deficient SrTiO3 layer seems to be highly reduced, which results in the absence of 440nm (blue-light) emission at 300K, and broad and weak 380nm emission at 20K. [Copyright &y& Elsevier]

Abstract: We fabricate epitaxial terbium iron garnet (Tb3Fe5O12, TbIG) thin films on (110) gadolinium gallium garnet (Gd3Ga5O12, GGG) substrates using a pulsed laser deposition technique. High quality (110) oriented epitaxial growth of TbIG thin films has been revealed by θ–2θ scans, φ-scans, rocking curves (ω-scans), and reciprocal space mapping in high resolution X-ray diffraction. Magnetic and magneto-optic hysteresis loops, however, demonstrate that the easy axis of magnetization in these films is out-of-plane, i.e. along [110] instead of [1–11] direction, as sharp contrast to bulk. [Copyright &y& Elsevier]

Abstract: We have reported the epitaxial growth and the electric/magnetic properties of SrRuO3 and (La0.67Sr0.33)MnO3 thin films on Ba(Ti0.925Zr0.075)O3 substrates. The dielectric constant and thermal expansion of Ba(Ti0.925Zr0.075)O3 exhibited hysteretic jumps at the structural transition temperatures. Near the rhombohedral to orthorhombic structural transition temperature of Ba(Ti0.925Zr0.075)O3, which occurs at ∼33 °C, we have observed a drastic jump of resistivity and magnetization of the thin films. These results suggest that epitaxial perovskite oxide thin films on Ba(Ti0.925Zr0.075)O3 substrates should be quite useful for the strain-induced changes of physical properties near room temperature. [Copyright &y& Elsevier]

Abstract: The photoconductivity spectra of oxygen-deficient SrTiO3−δ thin films with Pt contacts show two intriguing peaks at and above the band gap (∼3.2 eV). The first (second) peak, located at (above) the band gap, shows hysteretic (linear) photocurrent–voltage characteristics with a long (short) relaxation time. In addition, the first (second) peak shows a weak (strong) dependence on the surface treatment of the substrate as well as the surrounding atmosphere. These results have been discussed in terms of the Schottky contact, built-in voltage, and trapping/recombination process. [Copyright &y& Elsevier]

Persistent storage symptoms after medication with alpha blocker decrease quality of life (QoL) and may disturb sexual activity. Therefore, we evaluated the effect of add on therapy with mirabegron in patient with benign prostatic hyperplasia (BPH) and persistent storage symptoms after treatment with tamsulosin. [Extracted from the article]