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961.
962.
G. Yildirim M. Akdogan A. Varilci C. Terzioglu 《Crystal Research and Technology》2010,45(11):1161-1165
Influences of the different annealing ambient (in air, 1 bar, 2 bar, 3 bar and 4 bar oxygen partial pressure) on the titanium dioxide (TiO2) thin films deposited on soda lime glass by standard radio frequency (rf) magnetron reactive sputtering method at 100 watt were investigated by means of X–ray diffractometer (XRD), ultra violet spectrometer (UV–vis), and Scanning Electron Microscopy (SEM). It was found that either optical properties or energy band gaps of the films enhanced with increase in the oxygen partial pressure up to 3 bar. The energy band gaps of the films (except for the film annealed in 4 bar oxygen partial pressure) became larger than the film annealed in atmospheric pressure. The best transmission was observed for the thin film annealed in 3 bar oxygen partial pressure. Moreover, not only was grain–like structure found to be more dominant than dot–like structure but also growth of anatase phase was observed instead of that of the rutile phase with increasing oxygen partial pressure up to 3 bar. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
963.
J.-Ph. Jay F. Le Berre S.P. Pogossian M.V. Indenbom 《Journal of magnetism and magnetic materials》2010,322(15):2203-2214
Two techniques of measurements of thin film magnetostriction are compared: direct, when changes of the substrate curvature caused by the film magnetization are controlled, and inverse (“indirect”), when the modification of the magnetic anisotropy induced by the substrate deformation (usually bending) is measured. We demonstrate how both the elastic strength of the substrate and the effective magneto-mechanical coupling between the substrate deformation and magnetic anisotropy of the film depend on different conditions of bending. Equations to be used for magnetostriction value determination in typical cases are given and critical parameters for the corresponding approximations are identified. 相似文献
964.
O. Idigoras 《Journal of magnetism and magnetic materials》2010,322(20):L57
We have studied the magnetization reversal of uniaxial Co(1 0 1 0) films as a function of the applied field orientation by means of magneto-optical Kerr effect microscopy. Hereby, we find that while stable intermediate domain states exist for most field directions, their occurrence is suppressed for field orientations along the easy axis of magnetization. To facilitate this study, we have developed a data extraction methodology that allows for the quantitative analysis and compact display of entire magnetization distribution field-sequences in a single picture. It furthermore allows for the automated data analysis to unambiguously distinguish magnetization rotation processes from field-induced domain formation. 相似文献
965.
L. Chen C. Lei Z.M. Zhou W. Ding 《Journal of magnetism and magnetic materials》2010,322(19):2834-2839
Giant magnetoimpedance (GMI) effect on NiFe thin film is very promising due to its application in developing the magnetic field sensors with highly sensitivity and low cost. In this paper, the single layered NiFe thin film and NiFe/Cu/NiFe thin film with a meander structure are prepared by the MEMS technology. The influences of sputtering parameters, film structure and conductor layer width on GMI effect in NiFe single layer and meander NiFe/Cu/NiFe film are investigated. Maximum of the GMI ratio in single layer and sandwich film is 5% and 64%, respectively. The results obtained are useful for developing the high-performance magnetic sensors based on NiFe thin film. 相似文献
966.
P. Chowdhury Harish C. Barshilia P.K. Mishra D.V. Sridhara Rao 《Journal of magnetism and magnetic materials》2010,322(21):3266-3270
To study the influence of oxygen impurities in the sputtering atmosphere on microstructure, and the magnetic and magnetotransport properties, thin films of Ni83Fe17 were deposited under dc magnetron sputtering technique into which regulated oxygen gas was introduced. The partial pressure of oxygen was varied from 2×10−7 to 3×10−6 mbar. X-ray diffraction patterns indicate the reduction of grain growth with increasing the oxygen partial pressure. The grain microstructure and the composition were confirmed through high resolution transmission electron microscopy attached with Scanning Transmission Electron Microscopy (STEM). Transition from canted to rectangular magnetic hysteresis loop was observed through magnetization measurements for samples prepared under higher oxygen partial pressure which implies the structural changes in the magnetic domain formation. These observations were further confirmed through the measurements of anisotropic magnetoresistance properties. 相似文献
967.
P. Beck 《Journal of magnetism and magnetic materials》2010,322(22):3701-3703
The Dzyaloshinskii-Moriya (DM) vectors arising from a fabrication induced perpendicular strain gradient in a film of bcc Fe are calculated by a combination of the ab initio density functional electron theory with a micromagnetic model. It is shown that even for large strain gradients the absolute values of the DM vectors are 1-2 orders of magnitude smaller than those calculated recently for a Fe bilayer on W(1 1 0). The breaking of the symmetry of the static and dynamic properties of a magnetic vortex with respect to its polarization is discussed for systems with DM interactions. 相似文献
968.
A single electron transistor based on the ordered nanodot arrays was reported. The gold nanoparticles self-assembled in the ordered mesoporous silica thin films were used as the Coulomb islands. The Coulomb blockade and Coulomb oscillation are demonstrated at room temperature, and the SIMON simulations are consistent with the experimental results. 相似文献
969.
T. Shapoval V. Metlushko M. Wolf V. Neu B. Holzapfel L. Schultz 《Physica C: Superconductivity and its Applications》2010,470(19):867-870
Low-temperature magnetic force microscopy (LT-MFM) was used to study the distribution of superconducting vortices in Nb above a square array of 1 μm-sized circular ferromagnetic dots in a magnetic-vortex state. The force that the MFM tip exerts on the individual vortex in the depinning process was used to estimate the spatial modulation of the pinning potential. It was found, that the superconducting vortices which are preferably located on top of the Py dots experience a pinning force, about 15 times stronger as compared to the pinning force in the pure Nb film. This strong pinning exceeds the repulsive interaction between the superconducting vortices and allows vortex clusters to be located above the dots. 相似文献
970.
Osvaldo Vigil Jesús Fandiño Francisco Cruz-Gandarilla 《Journal of Physics and Chemistry of Solids》2010,71(3):404-406
The physical properties of the etched CdTe surfaces obtained during the process of formation of a p+ region on CdTe surface films using (i) a nitric/phosphoric acid mixture and (ii) a chemical Te-deposition method involving thermal annealing have been compared in this study. This study suggests the chemical-deposition method as an alternative to the chemical-etching methods for use in back-contact technology to increase the efficiency of CdTe solar cells. 相似文献