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We measured the electrical resistivity under magnetic field and pressure and de Haas van Alphen (dHvA) oscillations in CeCu 6 . The A value in the Fermi liquid relation of the electrical resistivity ρ = ρ 0 + AT 2 and the cyclotron effective mass are reduced with increasing magnetic fields and pressures. The A value, however, becomes distinct and/or is enhanced at the metamagnetic field, especially, in a characteristic pressure region where the electronic state deviates from the heavy fermion state, for example, at 2.00 GPa.

We studied an effect of pressure on the heavy fermion state of YbCo 2 Zn 20 under magnetic fields. The critical pressure P c , where the electronic state changes from the heavy fermion state to the antiferromagnetic state, is estimated to be P c 1.8 GPa. The super-heavy fermion state in the P c region is found to be strongly destroyed in magnetic fields for H 100 . The field-induced quadrupolar phase, which is most likely realized only for H 111 , is found to be robust even in the antiferromagnetic pressure region.