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arXiv · 1810.06845

Polarized neutron channeling in weakly magnetic films

S. V. Kozhevnikov·V. D. Zhaketov·T. Keller·Yu. N. Khaydukov·F. Ott·F. Radu
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Abstract

We describe a new sensitive method for the investigation of weakly magnetic films placed inside a tri-layer planar waveguide. Polarized neutrons tunnel into the waveguide through the surface, channel along the layers and are emitted from the end face as a narrow and slightly divergent microbeam. Polarization analysis permits to detect very small magnetization in the order of a few 10 Gauss. The magnetic film containing the rare-earth element Tb was investigated using both fixed wavelength and time-of-flight polarized neutron reflectometers. The experimental results are presented and discussed.

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S. V. Kozhevnikov, V. D. Zhaketov, T. Keller, Yu. N. Khaydukov, F. Ott, F. Radu. 2018-10-16. Polarized neutron channeling in weakly magnetic films. https://doi.org/10.1016/j.nima.2019.02.022

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