Magneto-oscillatory phenomena in double quantum wells with asymmetric scattering. I. Density of states and thermodynamic quantities

The one-particle Green’s function, the density of states, and the thermodynamic quantities (susceptibility and specific heat) are evaluated for tunnel-coupled quantum wells with asymmetric scattering in the presence of a transverse quasiclassical magnetic field. The oscillations of the susceptibility and of the specific heat have different periods and widths and depend sensitively on the level splitting between the left and right levels. Peculiar characteristics appear in the density of states when the splitting due to tunneling is comparable to the difference in the broadening between wells of equal width. When the tunneling splitting is stronger than this difference two sets of peaks arise with the same width. In the opposite case, the peaks have different widths but are superposed.