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arXiv · 1602.08263

Microscopic mechanism of the giant magnetocaloric effect in MnCoGe alloys probed by XMCD

F. Guillou·F. Wilhelm·O. Tegus·A. Rogalev
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Abstract

One important aspect of the magneto-structural transition in MnCoGe and related materials is the reduction in saturation magnetization from the orthorhombic to the hexagonal phase. Here, by combining an element specific magnetization probe such as x-ray magnetic circular dichroism and band structure calculations, we show that the magnetic moment instability between orthorhombic and hexagonal structures originates from a reduction in the Mn sub-lattice magnetization. The consequences of the moment instability for the magnetocaloric effect are discussed.

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F. Guillou, F. Wilhelm, O. Tegus, A. Rogalev. 2016-02-26. Microscopic mechanism of the giant magnetocaloric effect in MnCoGe alloys probed by XMCD. https://doi.org/10.1063/1.4944643

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