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arXiv · 1003.1206

Giant magneto-elastic coupling in a metallic helical metamagnet

A. Barcza·Z. Gercsi·K. S. Knight·K. G. Sandeman
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Abstract

Using high resolution neutron diffraction and capacitance dilatometry we show that the thermal evolution of the helimagnetic state in CoMnSi is accompanied by a change in inter-atomic distances of up to 2%, the largest ever found in a metallic magnet. Our results and the picture of competing exchange and strongly anisotropic thermal expansion that we use to understand them sheds light on a new mechanism for large magnetoelastic effects that does not require large spin-orbit coupling.

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A. Barcza, Z. Gercsi, K. S. Knight, K. G. Sandeman. 2010-05-25. Giant magneto-elastic coupling in a metallic helical metamagnet. https://doi.org/10.1103/physrevlett.104.247202

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