Reply to ‘‘Comment on ‘Radiative recombination processes of the many-body states in multiple quantum wells’ ’’

In the preceding Comment, Hillmer, Hansmann, and Forchel discussed possible mechanisms for the spatial expansion of a photodegenerated electron-hole plasma (EHP) in quantum wells. Although not the major topic of our paper [Phys. Rev. B 42, 2893 (1990)], we agree that excitonic and EHP lateral transport depends strongly on temperature, carrier density, and heterostructure configuration. Our recent results on ${\mathrm{Ga}}_{\mathit{x}}$${\mathrm{In}}_{1\mathrm{-}\mathit{x}}$As/${\mathrm{Al}}_{\mathit{y}}$${\mathrm{In}}_{1\mathrm{-}\mathit{y}}$As multiple quantum wells on InP substrate support the idea that wave-guided reabsorption and reemission of the luminescence is responsible for the observed light transport along the crystal surface.