Quantum interference effects in the induced currents in metallic LaB6 are investigated in pulsed magnetic fields extending to 60 T and to temperatures of up to 70 K. One of the quantum interference frequencies, corresponding to an area in k space equal to the Brillouin zone, has an effective mass precisely equal to zero. The attenuation of this and other frequencies at high temperatures requires the scattering effects of phonons to be considered within the Boltzmann transport equation. © 1998 The American Physical Society.

We report susceptibility experiments in magnetic fields up to 60 T and show conclusively that the de Haas-van Alphen oscillations originate from a single spin Fermi surface. New observed frequencies present in magnetic breakdown and quantum interference oscillations indicate that the Fermi-surface topology changes as a function of the applied field while maintaining a constant volume. These results are not expected from the Anderson lattice model. © 1998 The American Physical Society.