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arXiv · 1712.04765

Co$_{2}$PtGa: A promising magnetic shape memory alloy with high martensite transition temperature

Tufan Roy·P. Devi·Sanjay Singh·S. R. Barman·Aparna Chakrabarti
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Abstract

In the present work, a combined theoretical and experimental study on Co$_{2}$PtGa Heusler alloy shows that it exhibits a martensite transition around 1320 K with a small thermal hysteresis (10 K). Dynamical stability of Co$_2$PtGa in the tetragonal phase has been established by the theoretically calculated phonon dispersion curves. Magnetization measurements suggest that this alloy is a ferromagnetic material with a saturation magnetic moment of 2.83 $\mu_B$/f.u. at 2 K, which is in excellent agreement with the value obtained from \textit{ab-initio} calculations (2.87 $\mu_B$/f.u.). Our present study demonstrates that Co$_{2}$PtGa is a promising material for high temperature magnetic shape memory application.

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Tufan Roy, P. Devi, Sanjay Singh, S. R. Barman, Aparna Chakrabarti. 2017-12-13. Co$_{2}$PtGa: A promising magnetic shape memory alloy with high martensite transition temperature. https://arxiv.org/abs/1712.04765

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