Absence of magnetic field dependence of the cyclotron effective masses of electrons on the Fermi surface of Pd

Abstract
The de Haas-van Alphen effect was used to search for a field-dependent many-body enhancement of the cyclotron effective mass in palladium, an effect suggested by experiments observing a depression of the electronic specific heat by a magnetic field. Sixteen orbits on the open hole, Γ- centered electron, and X-centered hole sheet of the Fermi surface of Pd were studied with the field-modulation technique in fields up to 15 T and at temperatures as low as 0.5 K. For the heavy-mass β and γ orbits on the open hole sheet we find effective masses approximately 15% higher than reported earlier, while results for the other orbits confirm earlier work. Within experimental error no field dependence in the cyclotron effective mass was found for any orbit, implying that a large reduction in the linear term of the specific heat by a magnetic field is not due to a suppression of spin fluctuations. In addition, the field dependence in the argument of the spin-splitting factor in the Lifshitz-Kosevich expression for the amplitude of the de Haas-van Alphen effect was measured for the α orbit on the open hole sheet. The small field dependence observed is inconsistent with a large suppression of spin fluctuations, but is consistent with high-field magnetization measurements.