Acta Physica Polonica B

Vol. 34, No. 2, February 2003, page 667

De Haas--Van Alphen Experiments in the Quantum Critical Region of Cerium and Uranium Compounds

Y. Onuki, R. Settai, S. Araki, M. Nakashima, H. Ohkuni, H. Shishido, A. Thamizhavel, Y. Inada, Y. Haga, E. Yamamoto, T.C. Kobayashi

When pressure is applied to the cerium and uranium compounds, their magnetic ordering temperatures are suppressed and become zero at a critical pressure Pc. Around Pc, non-Fermi liquid and/or superconductivity are observed. We clarified a change of the electronic state via the de Haas--van Alphen (dHvA) experiment when pressure crosses Pc. The dHvA experiment under pressure was done for antiferromagnets CeRh2Si2, CeRhIn5 and URu2Si2, and a ferromagnet UGe2. We find an abrupt change of the Fermi surface for CeRh2Si2 and UGe2 when crossing Pc, indicating a first-order like phase transition. For CeRhIn5 and URu2Si2, a change of the cyclotron mass is clearly observed.

PACS numbers: 71.27.+a, 71.18.+y

  Paper (gzipped PostScript  1582 KB)
 
Table of Contents Back to Number 2 contents