Asymmetric magnetoresistance in bulk In-based off-stoichiometric Heusler alloys

It has been found that Ni50Mn35In14B exhibits with increasing temperature a first-order magnetostructural phase transition from a low-magnetization martensitic phase to a high-temperature ferromagnetic austenitic phase at T-M similar to 315 K as observed from magnetization M(T) curves with H=0.05 T. A shift in T-M of about 12 K towards lower temperatures has been detected under application of a 5T magnetic field. An asymmetric magnetoresistance (spin-valve-like behavior) has been observed in the vicinity of T-M at 304 K after the initial application of magnetic field that could be related to the kinetic arrest and de-arrest of a fractional austenite phase in the vicinity of phase co-existence. A possible origin of a spin-valve-like MR in Ni50Mn35In14B, and its relation to structural, magnetic, and magnetocaloric properties, has been discussed. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim