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arXiv · 1503.04276

Effect of composition on magnetocaloric properties of Mn$ _{3} $Ga$ _{(1-x)} $Sn$ _{x} $C

E. T. Dias·K. R. Priolkar·O. Cakir·M. Acet·A. K. Nigam
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Abstract

A study investigating the effect of Sn substitution on the magnetocaloric properties of Mn$ _{3} $Ga$ _{(1-x)} $Sn$ _{x} $C compounds reveals that nature of the MCE has a strong dependence on the nature of the magnetic ordering. For small amounts of Sn ($ x\leq0.2 $) the MCE is of the inverse type wherein an increase in the applied field beyond 5T gives rise to a table like temperature dependence of the entropy due to a coupling between the first order FM - AFM transition and the field induced AFM - FM transition. Replacement of Ga by larger concentrations of Sn ($ x\geq0.71 $) $(\Delta S_M)$ results in a change of the MCE to a conventional type with very little variation in the position of $(\Delta S_M)_{max}$ with increasing magnetic field. This has been explained to be due to the local strain introduced by A site ions (Ga/Sn) which affect the magnetostructural coupling in these compounds.

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E. T. Dias, K. R. Priolkar, O. Cakir, M. Acet, A. K. Nigam. 2015-03-14. Effect of composition on magnetocaloric properties of Mn$ _{3} $Ga$ _{(1-x)} $Sn$ _{x} $C. https://doi.org/10.1063/1.4916095

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