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arXiv · 2304.03033

Formation of Core-Shell Precipitates in off-stochiometric Ni-Mn-Sn Heusler alloys probed through the induced Sn-moment

Benedikt Eggert·Aslı Çakır·Damian Günzing·Nicolas Josten·Franziska Scheibel·Richard A. Brand·Michael Farle·Mehmet Acet·Heiko Wende·Katharina Ollefs
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Abstract

The Shell-ferromagnetic effect originates from the segregation process in off-stochiometric Ni-Mn-based Heusler. In this work, we investigate the precipitation process of L2$_1$-ordered Ni$_2$MnSn and L1$_0$-ordered NiMn in off-stochiometric Ni$_{50}$Mn$_{45}$Sn$_{5}$ during temper annealing, by X-ray diffraction (XRD) and $^{119}$Sn M\"ossbauer spectroscopy. While XRD probes long-range ordering of the lattice structure, M\"ossbauer spectroscopy probes nearest-neighbour interactions, reflected in the induced Sn magnetic moment. As shown in this work, the induced magnetic Sn moment can be used as a detector for microscopic structural changes and is, therefore, a powerful tool for investigating the formation of nano-precipitates. Similar research can be performed in the future, for example, on different pinning type magnets like Sm-Co or Nd-Fe-B.

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Benedikt Eggert, Aslı Çakır, Damian Günzing, Nicolas Josten, Franziska Scheibel, Richard A. Brand, Michael Farle, Mehmet Acet, Heiko Wende, Katharina Ollefs. 2023-04-06. Formation of Core-Shell Precipitates in off-stochiometric Ni-Mn-Sn Heusler alloys probed through the induced Sn-moment. https://arxiv.org/abs/2304.03033

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