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The Zn1 - x {\ {Co}}_xO and Zn1 - xCoxNyO1 -y thin films were grown by RF magnetron co-sputtering, but in different sputtering gases (Ar and N2O, respectively). X-ray diffraction analysis indicated that all the samples had c-axis preferred orientation, without any segregated secondary phase. UV–visible spectroscopy and X-ray photoelectron spectroscopy showed that Co^2 + ions substituted tetrahedrally coordinated Zn^2 + ions site for the films. The electrical and magnetic properties were investigated by the Hall effect and superconducting quantum interference device (SQUID) measurements, respectively. The Zn1 - x {\ {Co}}_xO had n-type conduction with electron concentration of 10^19 cm^- 3, and exhibited paramagnetism. Due to the charge compensation by N doping, the Zn1 - xCoxNyO1 -y possessed large resistivity, and also presented paramagnetism, besides the film Zn1 - xCoxNyO1 -y (x = 0.0162, y = 0.0004), which possessed room temperature ferromagnetism (RTFM). [ABSTRACT FROM AUTHOR]

In this paper, the complex impedance spectroscopy (CIS) of La0.67Sr1.33MnO4 and La0.67Sr0.33MnO3 were applied to characterize the ac properties below and above Neel temperature and/or Curie temperature, respectively. We demonstrate that the CIS can be sensitively affected by magnetic states on the manganite thin films. Our result provides further understanding of the dielectrics variation during the phase transition from an antiferromagnetic (AFM) insulating phase and/or a ferromagnetic metallic phase to a paramagnetic PM metallic phase. The CIS was analyzed based on an equivalent circuit model. The results imply that the specific feature of impedance can be attributed to the interplay of dielectric relaxations with the magnetic states at an alternative electromagnetic field. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the magnetic properties and local structures of discontinuous-Co70Fe30(x Å)-Zno multilayers (MLs). With the variation of Co70 Fe30 nominal thickness, the phase transition from diluted magnetic semiconductor (DMS) phase, x = 1 ML, to granular phase, x = 5, and 9 MLs, is indicated from the measurements of magnetization versus temperature behavior and extended X-ray absorption fine structure (EXAFS) on Co or Fe K-edge. The analysis of EXAFS at Zn K-edge shows the reduction of Co coordination numbers with the increasing CoFe thickness. This result demonstrates that the CoFe grain size plays an important role in the formation of DM8 and is greatly critical for multilayer growth technique. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the influence of temperature on the behavior of the step-induced magnetic anisotropy of a permalloy film. Measurement of the hysteresis loops; Analysis of the saturation magnetization of the thin film; Calculation of the anisotropy constant.