Effects of electric field on the exciton linewidth broadening due to scattering by free carriers in semiconducting quantum-well structures

The effects of an applied electric field perpendicular to the well layers on the broadening of the exciton linewidth due to scattering by free carriers in semiconducting quantum well (QW) structures is theoretically investigated based on a finite confining potential model. The dependence of the free carrier-exciton linewidth broadening on carrier concentration, temperature, and well width are calculated and discussed for various electric field strengths. It is found that the influence of the electric field on the linewidth broadening is appreciable in wide wells, while in narrow wells little change is shown even in the presence of a strong electric field.