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arXiv · 1907.05189

Ordered structure of FeGe$_2$ formed during solid-phase epitaxy

B Jenichen·M Hanke·S Gaucher·A Trampert·J Herfort·H Kirmse·B Haas·E Willinger·X Huang·S C Erwin
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Abstract

Fe$_{3}$Si/Ge(Fe,Si)/Fe$_{3}$Si thin film stacks were grown by a combination of molecular beam epitaxy and solid phase epitaxy (Ge on Fe$_{3}$Si). The stacks were analyzed using electron microscopy, electron diffraction, and synchrotron X-ray diffraction. The Ge(Fe,Si) films crystallize in the well oriented, layered tetragonal structure FeGe$_{2}$ with space group P4mm. This kind of structure does not exist as a bulk material and is stabilized by solid phase epitaxy of Ge on Fe$_{3}$Si. We interpret this as an ordering phenomenon induced by minimization of the elastic energy of the epitaxial film.

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B Jenichen, M Hanke, S Gaucher, A Trampert, J Herfort, H Kirmse, B Haas, E Willinger, X Huang, S C Erwin. 2019-07-11. Ordered structure of FeGe$_2$ formed during solid-phase epitaxy. https://doi.org/10.1103/physrevmaterials.2.052402

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