Abstract: We investigate the binding energies of excitons in a strained (111)-oriented zinc-blende GaN/Al0.3Ga0.7N quantum well screened by the electron-hole (e-h) gas under hydrostatic pressure by combining a variational method and a self-consistent procedure.A built-in electric field produced by the strain-induced piezoelectric polarization is considered in our calculations.The result indicates that the binding energies of excitons increase nearly linearly with pressure, even though the modification of strain with hydrostatic pressure is considered, and the influence of pressure is more apparent under higher e-h densities.It is also found that as the density of an e-h gas increases, the binding energies first increase slowly to a maximum and then decrease rapidly when the e-h density is larger than about 1e11cm-2.The excitonic binding energies increase obviously as the barrier thickness decreases due to the decrease of the built-in electric field.

Key words: exciton, strained zinc-blende quantum well, pressure, screened effect