MAGNETORESISTANCE AND DE-HAAS-VAN-ALPHEN OSCILLATION IN NORMAL AND SUPERCONDUCTING CERU2

We have succeeded in growing high-quality single crystals of CeRu2 and have measured the magnetoresistance and de Haas-van Alphen (dHvA) eff ect in both its normal and its superconducting mixed states. From the result of the magnetoresistance, we conclude that CeRu2 is a compensat ed metal. The measured dHvA frequencies are well explained by the resu lts of band-structure calculations. The dHvA frequency does not change in magnitude between the normal and superconducting mixed states, whi le the cyclotron mass is reduced, and the corresponding Dingle tempera ture increases in the mixed state. The mass and the Dingle temperature strongly depend on the magnetic field in the mixed state.