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arXiv · 1410.2767

New insights for the description of magnetic correlations inferred from muSR

P. Dalmas de Reotier·A. Yaouanc·A. Maisuradze
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Abstract

Whenever a compound exhibits a spontaneous muSR oscillation, long-range magnetic ordering is usually inferred. Here we show that some caution is required. The coherence length needs not to be large for a spontaneous muon spin precession to be observed. Establishing the incommensurate nature of a magnetic structure, solely based on muSR measurements, may not be reliable. The absence of a spontaneous muon precession at low temperature does not mean that the system under investigation does not display long-range magnetic ordering. The relaxation measured in zero and longitudinal field in the quasi-static limit is usually analyzed in the framework of the strong-collision model, the static polarization function being taken to be the famous Kubo-Toyabe function. This might not be satisfactory if short-range correlation effects are strong. Here we propose a method based on the maximum entropy concept and reverse Monte Carlo technique which gives results consistent with those obtained in 2013 by analytical means for the considered example.

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P. Dalmas de Reotier, A. Yaouanc, A. Maisuradze. 2014-10-10. New insights for the description of magnetic correlations inferred from muSR. https://doi.org/10.1088/1742-6596%2F551%2F1%2F012005

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