Many-body effects for a quasi-two-dimensional electron-hole plasma including finite well-width

By dealing with the many-body effects and the valence-band nonparabolicity, we discuss the ground-state energy as a function of the sheet carrier dens ity and the well-width for a quasi-two-dimensional quantum well system. The many-body effects due to exchange interaction and Coulomb correlation are evaluated within the random-phase approximation. Such evaluation includes t he solving of the Luttinger-Kohn Hamiltonian, which leads to obtaining the valence band structure. We observe that the dynamical correction of the Cou lomb correlation is comparable with the exchange energy at the Fermi edge a nd therefore the correlation effects play an important role in determinatio n of the ground-state energy Also, it is shown that the ground-state energy depends on the well-width and the sheet carrier density.