Abstract

The large exciton binding energy in wide-gap semiconductors and quantum wells favors ex-citonic gain processes for which no satisfactory theoretical treatment exists,¹ A knowledge of the balance between excitons and free carriers is crucial in determining the dominant gain process. It is known that a naive application of the Mott criterion for the metal-insulator transition as well as the use of a law of mass action are insufficient, as screening of excitons by the electron-hole plasma and strong scattering of particles within the plasma both play a crucial role.²

© 1998 Optical Society of America