Spin density wave order and fluctuations in Mn3Si: a transport study

TL;DR

This transport study of Mn3Si reveals the characteristics of spin density wave order and fluctuations, showing anomalies at the transition and a broad fluctuation regime extending well above T_N, with implications for understanding SDW materials.

Contribution

First comprehensive transport analysis of Mn3Si highlighting SDW order, fluctuations, and comparison with other SDW materials, revealing generic features.

Findings

Pronounced anomalies at SDW transition in resistivity, Hall, Seebeck, and Nernst effects.

Evidence of a large fluctuation regime extending up to ~200K.

Features of Mn3Si are similar to other prototype SDW materials like LaFeAsO and Chromium.

Abstract

We present a comprehensive transport investigation of the itinerant antiferromagnet Mn3Si which undergoes a spin density wave (SDW) order below T_N~21.3K. The electrical resistivity, the Hall-, Seebeck and Nernst effects exhibit pronounced anomalies at the SDW transition, while the heat conductivity is phonon dominated and therefore is insensitive to the intrinsic electronic ordering in this compound. At temperatures higher than T_N our data provide strong evidence for a large fluctuation regime which extends up to ~200K in the resistivity, the Seebeck effect and the Nernst effect. From the comparison of our results with other prototype SDW materials, viz. LaFeAsO and Chromium, we conclude that many of the observed features are of generic character.