Absolute de Haas-van Alphen amplitudes and g -factor measurements in Au using the wave-shape-analysis technique

A technique of de Haas-van Alphen (dHvA) wave-shape analysis is described and used to determine the absolute amplitude of the $〈111〉$ neck and $〈110〉$ dog-bone oscillations in pure Au. Only relative amplitude and phase measurements of the first and second dHvA harmonics are required. The technique projects out separately both the Lifshitz-Kosevitch dHvA second-harmonic content, and that due to magnetic interaction effects. Measured dHvA absolute amplitudes are used to directly determine electronic cyclotron-averaged g factors, with the result that gc=1.04±0.03 for the $〈111〉$ neck orbit and gc=2.04±0.28 for the $〈110〉$ dog-bone orbit. The result for the neck orbit is about 15% less than that obtained by Randles; there have been no previous g-factor determinations for the $〈110〉$ dog-bone orbit in the noble metals. The problem of experimentally determining the effective demagnetizing factor of a nonellipsoidal sample is discussed.