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

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 less than or equal to 0.2) 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 more than or equal to 0.71) (delta SM) results in a change of the MCE to a conventional type with very little variation in the position of (delta SM )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.