Nonvariational numerical calculations of excitonic properties in quantum wells in the presence of strain, electric fields, and free carriers

In this paper we describe the properties of effective-mass excitons in quantum wells in the presence of strain, transverse electric fields, and free carriers using a nonvariational numerical technique. The technique allows us to avoid the use of a prechosen form for the excitonic wave function and can be applied to arbitrarily shaped quantum wells with external perturbations. We describe the valence band within the effective-mass approximation using a 4×4 k⋅p Hamiltonian which neglects the split-off band; the conduction band is assumed to be parabolic. Results are presented for exciton binding energies, wave functions, and oscillator strengths.