J. Phys. IV France 07 (1997) C1-281-C1-282
The Thermoelectric Power of Ferromagnetically Ordered Cu1-xGaxCr2Se4 SpinelsT. Gron1, K. Bärner2, Ch. Kleeberg2 and I. Okonska-Kozlowska3
1 University of Silesia, Institute of Physics, ul. Uniwersytecka 4, 40-007 Katowice, Poland
2 Universität Göttingen, IV. Physik Institut, Bunsenstr. 11-15, 37073 Göttingen, Germany
3 Silesian University, Institute of Chemistry, Szkolna 9, 40-007 Katowice, Poland
Single crystals of Cu1-xGaxCr2Se4 have been prepared using a chemical vapor method. The absolute thermoelectric power S and the electrical resistivity ρ of single crystals with compositions x = 0.036, 0.158, 0.374, 0.394, have been measured in the temperature range from 5 to 400K. Al1 compounds are p-type metallic conductors with the residual resistance increasing with increasing gallium concentration. The temperature dependence of the resistivity is almost constant for temperatures T < Tc and increases close to the Curie temperature Tc, indicating a spin scattering contribution. A broad hump ΔS(T) which goes to zero close to Tc apparently is superimposed on a linear diffusion thermopower, suggesting magnon drag.
© EDP Sciences 1997