Magnetoresistance and Magnetocaloric Effect at a Structural Phase Transition from a Paramagnetic Martensitic State to a Paramagnetic Austenitic State in Ni50Mn36.5In13.5 Heusler Alloys

It is established, using magnetization measurements, that Ni50Mn36.5In13.5 is in a paramagnetic state (PS) above and below the martensitic transition temperature (TM). Magnetoresistance (MR) and magnetic entropy changes (ΔSM) in the vicinity of TM were studied. MR and ΔSM at TM were found to be ≈−8% and ≈ +24 J Kg−1 K−1, respectively, at ΔH = 5 T. Although MR and ΔSM values were lower than compared to those found in other Heusler systems, the significantly smaller hysteresis observed in Ni50Mn36.5In13.5 makes this compound, and other such compounds that undergo a martensitic transition in a PS, promising for the study and applications of magnetocaloric magnetic materials