New insights for the description of magnetic correlations inferred from muSR

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.

arXiv commentTo appear in the proceedings of the 13th International Conference on Muon Spin Rotation, Relaxation and Resonance, Grindelwald, Switzerland, 1-6 June 2014

References in corpus (3)

• First Order Transition in the Spin Dynamics of Geometrically Frustrated Yb2Ti2O7
• Spin dynamics and magnetic order in magnetically frustrated Tb2Sn2O7
• Short-range magnetic ordering process for the triangular lattice compound NiGa2S4: a positive muon spin rotation and relaxation study

Cited by in corpus (4)

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• On the robustness of the MnSi magnetic structure determined by muon spin rotation
• Magnetic order, spin waves and fluctuations in the triangular antiferromagnet La2Ca2MnO7