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تسجيل مستخدم جديدNonresonant microwave absorption in epitaxial La-Sr-Mn-O films and its relation to colossal magnetoresistance
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We study magnetic-field-dependent nonresonant microwave absorption and dispersion in thin La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ films and show that it originates from the colossal magnetoresistance. We develop the model for magnetoresistance of a thin ferromagnetic film in oblique magnetic field. The model accounts fairly well for our experimental findings, as well as for results of other researchers. We demonstrate that nonresonant microwave absorption is a powerful technique that allows contactless measurement of magnetic properties of thin films, including magnetoresistance, anisotropy field and coercive field.
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We studied magnetic-field induced microwave absorption in 100-200 nm thick La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ films on SrTiO$_{3}$ substrate and found a low-field absorption with a very peculiar angular dependence: it appears only in the oblique field and
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We have studied the electronic structure of epitaxially grown thin films of La$_{1-x}$Sr$_x$FeO$_3$ by {it in-situ} photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS) measurements. The Fe 2$p$ and valence-band PES spectra and th
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We have used high-resolution Extended X-ray Absorption Fine-Structure and diffraction techniques to measure the local structure of strained La$_{0.5}$Sr$_{0.5}$CoO$_3$ films under compression and tension. The lattice mismatch strain in these compound
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