The relationship between the asymmetric magnetoresistive effect and the magnetocaloric effect in NiCoMnCrSn Heusler alloys.

The correlation between the magnetocaloric effect and magnetotransport property was investigated in NiCoMnCrSn Heusler alloys. The asymmetric isothermal-magnetoresistance around the phase transformation temperature was observed, from which a parameter γ, determined as the ratio of the asymmetric magnetoresistance to the temperature coefficient of resistance, is proposed. According to Maxwell's equation, the parameter γ is analyzed to be equivalent to the transformation temperature change induced by a magnetic field in martensitic transformation. This finding is confirmed by experimental results. In addition, the γ values can be used to estimate the magnetic entropy change of the martensitic transformation directly without measuring the comprehensive temperature dependence of magnetization curves.