Theory of the de Haas-van Alphen Effect for a System of Interacting Fermions

The de Haas-van Alphen effect for a system of interacting fermions is investigated. It is shown that, granting certain analytic properties (which were used before in establishing the existence of a Fermi surface, and which have only been established in the sense of perturbation theory), it is possible to obtain a simple expression for the oscillatory part of the thermodynamic potential. In particular, one finds that the de Haas-van Alphen oscillations have the same amplitude and period as in the usual quasi-particle picture, but that the phase is given by a more complicated proceedure.