抄録
The resistivity of CoS2 having the pyrite structure was measured between 4.2 K and 300 K under pressure up to 18 kbar and under magnetic field up to 45 kOe. The hump anomaly just below the Curie temperature (Tc) was found to become sharper with decreasing Tc by pressure and to become sluggish with increasing Tc by field. The magnetization (M) dependence of both the hump anomaly below Tc and a positive magnetoresistance above Tc was empirically analyzed, which resulted in M2 dependent effective mass. The spontaneous and induced volume-strictions were also measured near Tc up to 45 kOe, the latter of which was found to vary as M2 for small M. These anomalies can be qualitatively understood through the variations of M and Tc in a unified way including the effect of impurity-doping.
