Screening of exciton states by quasi-two-dimensional electron gas in quantum wells

Abstract

Changes in the binding energy and oscillator strength of an exciton state due to screening by a quasi-two-dimensional electron gas were calculated self-consistently in a nonlinear approximation. It was shown that the collapse of the bound state proceeds at very small concentrations N s ≃5×109 cm−2, which is a consequence of taking into account the nonlinearity of the system response to the Coulomb perturbation.