Structural, magnetic, and magnetotransport studies in bulk Ni55.2Mn18.1Ga26.7 alloy

Structural, magnetic, and transport properties have been investigated in off-stochiometric bulk Ni55.2Mn18.1Ga26.7 alloy. The alloy undergoes an austenite-martensite phase transition in ferromagnetic state at 264 K. The temperature and field dependence of electrical resistivity studies revealed that the electron-electron scattering is dominant in determining the resistivity below 80 K, while at higher temperatures (80-300 K), electron-magnon as well as electron-phonon scattering dominate. A negative magnetoresistance value of 7% maximum near T-C (similar to 283 K) at 7 T field has been obtained in the alloy. Also a magnetocaloric value (Delta S-M) of -1.3 J/kg K has been observed at around 264 K.