Electrical resistivity and thermopower of Y_1-xPr_xCo₂Compounds

Abstract

Electrical resistivity ρ and thermopower S of the pseudo-binary compounds of Y1-xPrxCo2 have been measured in the temperature range between 2 and 300 K under magnetic fields up to 10 T, together with the pressure measurements of ρ and S in Y0.4Pr0.6Co2. The Curie temperature decreases with decreasing x, and vanishes at the critical composition xc ≈ 0.4, where the residual resistivity attains a maximum value. The Curie temperature and the residual resistivity of Y0.4Pr0.6Co2 show the same pressure dependence as those of the heavy-rare-earth based compounds. These behaviors of ρ and S indicate the inhomogeneous distribution of the Co 3d magnetization. The magnetoresistance of the light-rare earth Y1-xPrxCo2 system is negative in the whole range of x, except for x = 0 and 1, which is a characteristic behavior related with magnetic state and magnitude of the effective field acting on the Co 3d subsystem.