Giant magnetoresistance and magnetocaloric effects of the Mn1.82V0.18Sb compound

A giant magnetoresistance effect in the Mn1.82V0.18Sb compound is reported, which is associated with a first-order metamagnetic transition from an antiferromagnetic to a ferrimagnetic state, induced by an external field. The largest GMR ratio equals 26% for Mn1.82V0.18Sb and is achieved at 250 K in a field of 5 T. The origin of the GMR effect is ascribed to the reconstruction of the Fermi surface due to the collapse of the super-zone gap after the metamagnetic transition. In addition, a magnetocaloric effect with a magnetic-entropy change of −5.5 J/kg K is observed in this compound around the magnetic transition temperature. [Copyright &y& Elsevier]