Anomalous temperature dependence of magnetic quantum oscillations in CeBiPt

Department of Quantum Matter, ADSM, Hiroshima University, Higashi-Hiroshima 739-8526, Japan(February 1, 2008)Shubnikov–de Haas (SdH) and Hall-effect measurements of CeBiPt and LaBiPt reveal the presenceof simple and very small Fermi surfaces with hole-like charge carriers for both semimetals. In themagnetic material, CeBiPt, we observe a strong temperature dependence of the SdH frequency. Thishighly unusual effect might be connected with an internal exchange field within the material and astrongly spin-dependent scattering of the charge carriers.PACS numbers: 71.20.Eh, 71.18.+y