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arXiv · 1101.3142

Martensite structures and twinning in substrate-constrained epitaxial Ni-Mn-Ga films deposited by a magnetron co-sputtering process

Jérémy Tillier·Daniel Bourgault·Sébastien Pairis·Luc Ortega·Nathalie Caillault·Laurent Carbone
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Abstract

In order to obtain Ni-Mn-Ga epitaxial films crystallized in martensite structures showing Magnetic-Induced Rearrangement (MIR) of martensite variants, a fine control of the composition is required. Here we present how the co-sputtering process might be helpful in the development of Ni-Mn-Ga epitaxial films. A batch of epitaxial Ni-Mn-Ga films deposited by co-sputtering of a Ni-Mn-Ga ternary target and a pure manganese target has been studied. The co-sputtering process allows a precise control of the film compositions and enables keeping the epitaxial growth of Ni-Mn-Ga austenite during deposition at high temperature. It gives rise to tune the content of the MIR-active 14-modulated martensite in the film at room temperature, as well as micro and macro-twinned domains sizes.

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Jérémy Tillier, Daniel Bourgault, Sébastien Pairis, Luc Ortega, Nathalie Caillault, Laurent Carbone. 2011-01-17. Martensite structures and twinning in substrate-constrained epitaxial Ni-Mn-Ga films deposited by a magnetron co-sputtering process. https://doi.org/10.1016/j.phpro.2010.11.094

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