De Haas–van Alphen effect in CeNi under pressure

Abstract

An intermediate valence compound CeNi exhibits a phase transition under pressure, which is associated with the γ–α transition in Ce. To clarify a change of the electronic state under pressure, we measured the de Haas–van Alphen (dHvA) effect under pressure up to 6 kbar using a Cu–Be pressure cell. The dHvA branches are still observed after the phase transition. The topology of the Fermi surface is therefore unchanged. The cyclotron effective mass is, however, reduced from 11 to 3.2 m 0 for branch ε and from 5.4 to 1.2 m 0 for branch σ when the pressure is changed from 1 bar to 3.7 kbar.