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The phase-sensitive microwave studies of thin epitaxial manganite La(sub 1-x)Sr(sub x)MnO3 films on SrTiO3 substrate is reported. The findings reveal that the dc and the microwave resistivity of the La0.8Sr0.2MnO3 are almost the same, while for the La0.7Sr0.3MnO3 they are different above 200 K.

Magnetic properties of Co2MnGe thin films of different thicknesses (13, 34, 55, 83, 100, and 200 nm), grown by rf sputtering at 400 °C on single crystal sapphire substrates, were studied using vibrating sample magnetometry and conventional or microstrip line ferromagnetic resonance. Their behavior is described assuming a magnetic energy density showing twofold and fourfold in-plane anisotropies with some misalignment between their principal directions. For all the samples, the easy axis of the fourfold anisotropy is parallel to the c-axis of the substrate while the direction of the twofold anisotropy easy axis varies from sample to sample and seems to be strongly influenced by the growth conditions. Its direction is most probably monitored by the slight unavoidable miscut angle of the Al2O3 substrate. The twofold in-plane anisotropy field Hu is almost temperature independent, in contrast with the fourfold field H4 which is a decreasing function of the temperature. Finally, we study the frequency dependence of the observed line-width of the resonant mode and we conclude to a typical Gilbert damping constant α value of 0.0065 for the 55-nm-thick film. [ABSTRACT FROM AUTHOR]

We report phase-sensitive microwave studies of thin epitaxial manganite La1-xSrxMnO3 films on SrTiO3 substrate. The measurements were performed in the temperature range of 80–330 K using a contactless microwave scanning probe operating at 26 GHz with the aim of comparing dc resistivity and microwave resistivity. We find that the dc and the microwave resistivity of the La0.8Sr0.2MnO3 are almost the same, while for the La0.7Sr0.3MnO3 they are different above 200 K. Our analysis of different mechanisms of this discrepancy, together with our measurement of the ferromagnetic resonance on the same samples, yields the film inhomogeneity on the microscopic scale as the most probable explanation. [ABSTRACT FROM AUTHOR]

The vibrating sample magnetometry technique is employed to explain the structural, static, as well as the dynamic magnetic properties of the [Co.sub.2]MnGe thin films grown by rf sputtering on the single crystal sapphire substrates. The direction of orientation of the twofold and fourfold in-plane anisotropies exhibited by the films is also analyzed.