Volume 91, Issue 10, 15 May 2002
Index of content:
Properties of epitaxial chromium dioxide films grown by chemical vapor deposition using a liquid precursor91(2002); http://dx.doi.org/10.1063/1.1455604View Description Hide Description
Epitaxialchromium dioxide films have been grown using chemical vapor deposition on (100) substrate with chromyl chloride as a liquid precursor. The films are extremely smooth (rms roughness less than 4.6 Å for a 1000-Å-thick film) and have the largest spin polarization yet observed, as determined by point contactAndreev reflection. Magnetization switching properties of the films are close to those of a single-domain particle. Preliminary results on the in situgrowth of exchange-biased multilayers are also reported. Although a bias field is observed, it is much smaller in comparison with the coercivity of the film.
Characterization of magnetoimpedance on polycrystalline and amorphous chromium oxides bilayered thin films91(2002); http://dx.doi.org/10.1063/1.1455605View Description Hide Description
The impedance of chemical vapor deposited and bilayered thin films, composed of polycrystalline and amorphousstructure, have been systematically studied in function of frequency and temperature. In the polycrystalline-- bilayer, the real part of impedance at low frequency demonstrates a sharp transition at temperature around 330 K, with a specific feature of positive temperature coefficient, similar to the variation of dc resistance occurs at ferroelectric-paraelectric transition in the ceramics. In contrast, the imaginary part of impedance, at frequency shows a characteristic of negative temperature coefficient. Further analysis of the frequency dependence of the impedance shows the contribution from the dynamics of both the dielectric and magnetic dipoles in the layers. Comparison of polycrystalline- and amorphous- single layer with the bilayer is discussed.
91(2002); http://dx.doi.org/10.1063/1.1448299View Description Hide Description
The magnetic and transport properties of magnetite thin filmsgrown epitaxially with a Ru underlayer on single crystal MgO (110) have been investigated. Epitaxialgrowth has been confirmed by x-ray diffraction(XRD). It has been shown that addition of a Ru underlayer affects in-plane magnetic anisotropy:grown directly on MgO exhibits an in-plane anisotropy, while grown on MgO/Ru does not. XRD results show that presence of Ru underlayer reduces tensile stress in the film. This difference in the stress explains the difference in the anisotropy of the films. Resistivity of the films with and without Ru underlayer both increases at low temperatures, but no clear Verway transition at 120 K was observed.