Metamagnetic Behaviour in CeCu6

Abstract

The metamagnetic behaviour, which corresponds to one of the characteristic properties in the heavy fermion compounds, was studied by measuring the electrical resistivity under pressure and magnetic field for a typical heavy fermion compound CeCu 6 with orthorhombic structure. The transverse magnetoresistance at 100 mK indicated a peak structure at H m = 20 kOe for the magnetic field H \varparallel c -axis under ambient pressure. H m is found to increase linearly as a function of pressure and indicates H m = 102 kOe at 1.75 GPa, for example. The quantum critical point is thus likely to exist at a slightly negative pressure value of ∼ 0.21 GPa from extrapolating H m to zero. The ρ 0 and A values in the electrical resistivity ρ= ρ 0 + A T 2 decrease steeply in magnitude with increasing pressure and magnetic field, indicating that the heavy fermion state is destroyed by pressure and magnetic field.