FERROMAGNETIC TRANSITION OF HEISENBERG FERROMAGNETIC METAL OF HOS2 - STATIC CRITICAL PROPERTIES

The static magnetic properties near the Curie temperature in CoS2 have been thoroughly studied by using various experimental techniques from high quality single crystals, which were grown by the chemical transport technique. A Very small anisotropy in magnetization confirms that CoS2 is the best system to apply the Heisenberg Hamiltonian. The critical indices obey the static scaling hypothesis, which indicates negligible effect of the temperature-induced local moment on the ferromagnetic transition. However, the static critical properties suggest that the magnetic transition is close to the tricritical point, although the magnetic transition in CoS2 is continuous.