Superconducting properties of CeRu2 single crystal

We have grown single crystals of superconductor CeRu 2 by a zone melting method, on which we have measured the lower and upper superconducting critical fields. They are estimated as 250-400 Oe and 74 kOe at 0 K, respectively. The upper critical field H c2 is slightly anisotropic, 64.8 kOe for the field along the direction and 65.6 kOe for at 1.5 K. We have also observed a characteristic feature in the superconducting mixed state.