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Abstract: The effect of nitrogen doping on optical properties and electronic structures of SrZrO3 (SZO) films was investigated both experimentally and theoretically. A shift of the absorption edge to the longer wavelength, i.e., the narrowing of the band gap caused by nitrogen doping was observed. The first-principles calculations revealed that the band gap reduced in nitrogen-doped SZO because of the localized N 2p states above O 2p states and the bottom of conduction band of Zr 4d shifting to a lower energy. [ABSTRACT FROM AUTHOR]

Abstract: Aurivillius-structured Bi4.15Nd0.85Ti3FeO15 multiferroic thin films with four perovskite slabs were deposited on Pt/Ti/ SiO2/Si substrates by the metal–organic decomposition method. The structural, dielectric and multiferroic properties of the films were investigated. Good ferroelectric behavior along with large dielectric constant and small loss factor were observed at room temperature. A weak ferromagnetic rather than an antiferromagnetic property was observed at room temperature by magnetic measurement. Moreover, the ferromagnetic property was enhanced when the temperature was below 13 K and a large saturation magnetization of about 5.4 emu/cm3 was obtained at 4 K. Possible reasons are put forward to discuss the complicated magnetic property. [ABSTRACT FROM AUTHOR]

Abstract: Sr1−x Pr x TiO3 films were prepared by metal organic deposition method on (111) Pt/Ti/SiO2/Si substrates. Pr-doping greatly improves the dc leakage behavior of the films. The samples with show excellent electric field frequency and temperature stability of dielectric properties, while the samples indicate an obvious dielectric relaxation behavior and better polarization versus applied electric field (–) hysteresis loops. These peculiar electrical properties can be explained mainly by the Pr-doping-induced changes in the free charge carriers, the lattice distortion, the charge transfer process and polar nanoregions. In addition, the variable valence of Pr ions may also have significant impacts. [Copyright &y& Elsevier]

Abstract: Dense and flat SrZrO3 films in an orthorhombic (Pbnm) perovskite phase are fabricated on fused quartz substrates via the metal organic decomposition method. Optical measurements show that the average transmittance of the films is about 90% for light with a wavelength longer than 240 nm, and the absorption edge of the films shifts to longer wavelengths with an increase of annealing temperature and film thickness. Meanwhile, first-principles calculations are performed by using an accurate Vienna ab initio simulation package to explore the electronic band structure of orthorhombic SrZrO3. The observed shift of the absorption edge could be well explained by the size effect on the band structure. [Copyright &y& Elsevier]

Abstract: KNb0.95Co0.05O3 (KN–Co) ceramic was prepared via a solid-state reaction method, and the effect of cobalt dopant on the structural, electric, and magnetic properties was studied. The KN–Co ceramic with polycrystalline perovskite structure exhibited ferromagnetic and ferroelectric properties simultaneously at room temperature, and the coupling of them was confirmed by a large magnetocapacitance effect (about 13%) near the Curie temperature. The possible causes for the magnetism and magnetoelectric properties are discussed. [Copyright &y& Elsevier]