Origin of the frequency branch γ of the de Haas-van Alphen effect in CeSn3

CeSn3 is a typical heavy-electron compound which belongs to the valence-fluctuation regime. The major experimental frequency branches of the de Haas-van Alphen effect are explained reasonably well by the large hole sheet and the large electron sheet of the Fermi surface which are derived on the basis of an itinerant 4f-electron model. In particular, it is shown by visualizing the extremal electron orbits that one of the major experimental frequency branches, i.e., the branch gamma, can be explained by those orbits which run through the small hollow on the large electron sheet. (C) 1998 Elsevier Science B.V. All rights reserved.