Magnetism and superconductivity in a heavy-fermion superconductor, CePt3Si

We have studied the magnetic and thermal properties of a single crystal of CePt3Si, which is a recently reported heavy-fermion superconductor with a superconducting transition temperature Tc = 0.75 K and a Neel temperature TN = 2.2 K. The overall experimental data are principally explained on the basis of the crystalline electric field (CEF) scheme. Even in the antiferromagnetic state, the CEF model applies well to the characteristic features in the magnetization curve. These results indicate the existence of a localized magnetic moment at the Ce site, with a considerably reduced ordered moment of 0.16 μB/Ce, and the strongly correlated conduction electrons are condensed into the superconducting state. We have also constructed the magnetic phase diagram including the superconducting phase for and [001].