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arXiv · 1405.0140

Understanding the $μ$SR spectra of MnSi without magnetic polarons

A. Amato·P. Dalmas de Réotier·D. Andreica·A. Yaouanc·A. Suter·G. Lapertot·I. M. Pop·E. Morenzoni·P. Bonfà·F. Bernardini·R. De Renzi
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Abstract

Transverse-field muon-spin rotation ($μ$SR) experiments were performed on a single crystal sample of the non-centrosymmetric system MnSi. The observed angular dependence of the muon precession frequencies matches perfectly the one of the Mn-dipolar fields acting on the muons stopping at a 4a position of the crystallographic structure. The data provide a precise determination of the magnetic dipolar tensor. In addition, we have calculated the shape of the field distribution expected below the magnetic transition temperature $T_C$ at the 4a muon-site when no external magnetic field is applied. We show that this field distribution is consistent with the one reported by zero-field $μ$SR studies. Finally, we present ab initio calculations based on the density-functional theory which confirm the position of the muon stopping site inferred from transverse-field $μ$SR. In view of the presented evidence we conclude that the $μ$SR response of MnSi can be perfectly and fully understood without invoking a hypothetical magnetic polaron state.

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A. Amato, P. Dalmas de Réotier, D. Andreica, A. Yaouanc, A. Suter, G. Lapertot, I. M. Pop, E. Morenzoni, P. Bonfà, F. Bernardini, R. De Renzi. 2014-05-01. Understanding the $μ$SR spectra of MnSi without magnetic polarons. https://doi.org/10.1103/physrevb.89.184425

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