Large magnetic entropy change in a Heusler alloy Ni52.6Mn23.1Ga24.3 single crystal -: art. no. 132412

A large magnetic entropy change \DeltaS\ has been observed in Heusler alloy Ni52.6Mn23.1Ga24.3 single crystal near the martensitic structural transition temperature of 300 K with applied field along [001] direction. The obtained \DeltaS\ under an applied field of 5 T reaches 18.0 J/Kg K (corresponding 146 mJ/cm(3) K). A more important result is that \DeltaS\ can achieve constant increase of 4.0 J/Kg K for the field increase of every tesla. The very large magnetic entropy change is attributed to the abrupt change of magnetization when the first-order martensitic-austensitic structural transition takes place. The phenomena of the large magnetic entropy change and the easy adjustment of the martensitic-austensitic transition-temperature indicate that the non-rare-earth based Ni-Mn-Ga single-crystal materials may have potential applications as magnetic refrigerants.