Large Magnetization and Reversible Magnetocaloric Effect at the Second-Order Magnetic Transition in Heusler Materials

In this contribution we have analyzed the Heusler class of materials looking for systems presenting large ground-state moments, which can be stabilized into a fully austenite state with a second-order phase transition around room temperature. We have pinpointed a composition, Ni2Mn1.4In0.6, which has been experimentally studied and shown to exhibit high and reversible magnetocaloric properties, comparable to the benchmark material for second order transition magentocaloric effect, Gadolinium. Based on the overview of the existing similar Heusler compounds together with additional first-principles calculations, we explain the underlying mechanisms and point out a perspective for further improvements. Thus, our study consists of a set of rules, and a proof of concept, for finding Heusler alloys showing a large ground-state magnetic moment and reversible MCE aiming at applications.