Exciton-phonon scattering: Competition between the bosonic and fermionic nature of bound electron-hole pairs

Semiconductor excitons are composite particles consisting of fermionic carriers. Nevertheless they are considered as paradigmatic candidates for bosonic condensation and the formation of macroscopic coherence in solids. To address both effects, the kinetics of exciton thermalization is studied, including their composite fermionic character. This way, exciton condensation based on the primary assumption of a bosonic thermalization is questioned. In this light, also discussed is whether a recently observed decrease of linewidths at increasing exciton density can be related to a signature for emerging excitonic coherence.