The Fermi Surface in Filled Skutterudite RFe 4P 12 (R=La and Nd)

We have investigated the de Haas-van Alphen (dHvA) effect and the transverse magnetoresistance in filled skutterudite LaFe 4 P 12 and NdFe 4 P 12 . The Fermi surface of LaFe 4 P 12 consists of a nearly spherical hole sheet and a multiply connected one. These features are explained reasonably well by a full potential linearized augmented-plane-wave (FLAPW) band structure calculation. The Fermi surface of NdFe 4 P 12 is similar to those in LaFe 4 P 12 except the exchange splitting in the dHvA frequencies. The cyclotron effective masses are enhanced roughly twice compared to those of LaFe 4 P 12 due to the electron-magnon interaction.