Magnetoresistance and magnetocaloric effect at a structural phase transition from a paramagnetic martensitic state to a paramagnetic austenitic state in Ni_(50)Mn_(36.5)In_(13.5) Heusler alloys

摘要

It is established, using magnetization measurements, that Ni_(50)Mn_(36.5)In_(13.5) is in a paramagnetic state (PS) above and below the martensitic transition temperature (T_M). Magnetoresistance (MR) and magnetic entropy changes (ΔS_M) in the vicinity of T_M were studied. MR and ΔS_M at T_M were found to be≈-8% and ≈+24 J Kg~(-1) K~(-1) respectively, at ΔH = 5 T. Although MR and ΔS_M values were lower than compared to those found in other Heusler systems, the significantly smaller hysteresis observed in Ni_(50)Mn_(36.5)In_(13.5) 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.