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Composition and temperature dependence of the thermoelectric power of Ni$_{2+x}$Mn$_{1-x}$Ga alloys

P. A. Bhobe·J. H. Monteiro·J. C. Cascalheira·S. K. Mendiratta·K. R. Priolkar·P. R. Sarode
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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 $\le$ x $\le$ 0.19). The samples have been characterized by a.c. 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.

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P. A. Bhobe, J. H. Monteiro, J. C. Cascalheira, S. K. Mendiratta, K. R. Priolkar, P. R. Sarode. 2006-10-27. Composition and temperature dependence of the thermoelectric power of Ni$_{2+x}$Mn$_{1-x}$Ga alloys. https://doi.org/10.1088/0953-8984%2F18%2F48%2F011

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