K-space Sampling Techniques Research Articles

Effects of the exciton continuum on resonant Raman scattering in GaAs quantum wells.

The effect of the exciton continuum on resonant Raman scattering in GaAs quantum wells is investigated. A k-space sampling technique is used to deal with exciton states, including the effects of valence-band mixing. Discrete and continuum exciton states are included in our calculation. We find that the resonant Raman spectra so obtained are in much better agreement with experiment compared with those that do not include the exciton continuum states.

Theory of line shapes of exciton resonances in semiconductor superlattices.

Realistic model calculations on the absorption spectra of semiconductor superlattices are presented. Emphasis is put on the analysis of line shapes of various peak structures arising from discrete excitonic states of one pair of subbands coupled with the excitonic (discrete and continuum) states associated with other pairs of subbands. The angle-dependent valence-band mixing and the final-state interaction effects are properly taken into account via the k-space sampling technique. Our results are in excellent agreement with recent high-resolution photoluminescence excitation spectra for a number of GaAs-${\mathrm{Al}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As quantum wells and superlattices.