A new experimental technique has been tested with Synchrotron Mössbauer Source in Mössbauer spectroscopy that relies on the polarisation analysis of reflected radiation. We have shown that with rotated polarisation, the dichroic components establish the scattering intensity in the resonant spectrum. In the reflected signal, the angular dependence of such a component is defined by a peak near the critical angle of the total external reflection. In the case of collinear antiferromagnetic interlayer ordering the "magnetic" maxima on the angular reflectivity curve, scattering with this rotated polarisation is basically only created. The first Mössbauer reflectivity experiment with rotated polarisation selection shows the anticipated near critical angle peak. With rotated polarisation near the critical angle, the measured Mössbauer reflectivity spectra (R-spectra) are very different from the Mössbauer R-spectra, measured without analysis of polarisation. They have a simpler shape and contain a smaller number of lines that, in the case of poorly resolved spectra, allow for better data interpretation. It is shown that the Mössbauer R-spectra with rotated polarisation is defined by the increased sensitivity of the surface, determined by the depth dependence of the "squared standing waves." Therefore, for investigations of surfaces, ultra-thin layers and multilayers with complex magnetic structures, the latest approach has fascinating perspectives.
Author(s) Details
Marina Andreeva
Faculty of Physics, M.V. Lomonosov Moscow
State University, 119991 Moscow, Russia.
Roman Baulin
Faculty of Physics, M.V. Lomonosov Moscow State University, 119991 Moscow,
Russia.
Aleksandr Chumakov
ESRF-The European Synchrotron, CS 40220, 38043 Grenoble Cedex 9, France and
National Research Institute”, Pl. Kurchatova 1, 123182 Moscow, Russia.
ESRF-The European Synchrotron, CS 40220, 38043 Grenoble Cedex 9, France.
View Book :- https://bp.bookpi.org/index.php/bpi/catalog/book/319
No comments:
Post a Comment