Screening and strain effects on the ground-state energy of a quasi-two-dimensional quantum well system

We discuss the screening and strain effects on the ground-state energy of t he strained-layer semiconductor quantum wells, which forms a quasi-two-dime nsional electron-hole plasma within the screened Hartree-Fock approximation . The exchange self-energy is evaluated within the Thomas-Fermi screening s cheme for variation of the sheet density and the biaxial compressive strain . Such evaluation includes the solving of the Luttinger-Kohn Hamiltonian, w hich leads to obtaining the valence band structure [Phys. Rev. 97, 869 (195 5)]. The dependence of the exchange self-energy on the sheet density and th e strain is shown to be significantly reduced as the screening effects are taken into account. Also, the screening plays an important role in determin ing the ground-state energy and the renormalization of the single-particle energies. In addition, we observe that the ground-state energy increases wi th the biaxial compressive strain. (C) 2001 American Institute of Physics.