On the influence of Sb concentration on the magnetization and magnetoresistivity in the spinel compounds CuCr2-xSbxS4 (where x = 0.3, 0.4, 0.5)

Powder samples of CuCr2-xSbxS4 were obtained for x=0.3, 0.4 and 0.5. All the samples have spinel structure. The magnetization measurements were carried out with the use of the induction method in the temperature range of 4.2-300 K in stationary fields with inductions up to 14 T. Both the electrical conductivity and the magnetoresistivity were measured in the same range of temperatures with the use of the four-point method. For the magnetoresistivity measurements both stationary fields up to 14 T and pulsed fields of 38 T were applied. A lack of magnetic saturation is observed for all the samples. Moreover, an increase of the antiferromagnetic component of the magnetization is observed with the increase of the Sb concentration. The absolute values of magnetoresistivity as a function of x exhibit at 4.2 K and 14 T a maximum at about x=0.4, assuming zero at x=0.5. For the two concentrations, i.e. for x=0.3 and 0.5, the magnetoresistivity at room temperature changes its sign twice as a function of the magnetic field. A peak clearly seen in the temperature dependence of the relative derivatives of both the magnetization and susceptibility seems to testify to a spin-flip transition at 13 K and 1 T