Composition and temperature dependence of the thermoelectric power of Ni(2+x)Mn(1-x)Ga alloys

Abstract

The thermoelectric power (TEP) measurements have been carried out to investigate the changes in the electronic structure associated with the intermartensitic and martensitic transitions in Ni(2+x)Mn(1-x)Ga (0 less than or equal to x less than or equal to 0.19). The samples have been characterized by ac magnetic susceptibility measurements. The correlation between the TEP and the microstructural changes sensitive to the increasing Ni content in Ni(2+x)Mn(1-x)Ga has been investigated. The changes in the density of states as reflected in the temperature variation of the TEP are consistent with the conclusions drawn from the Jahn Teller mechanism of lattice distortion.