Excitons dressed by a sea of excitons

  title={Excitons dressed by a sea of
  author={Monique Combescot and O. Betbeder-matibet},
  journal={The European Physical Journal B - Condensed Matter and Complex Systems},
Abstract.We here consider an exciton i embedded in a sea of N identical excitons 0. If the excitons are taken as true bosons, a bosonic enhancement factor N is found for i=0. If the exciton composite nature is kept, this enhancement not only exists for i=0, but also for any exciton having a center of mass momentum equal to the sea exciton momentum. This physically comes from the fact that an exciton with such a momentum can be transformed into a sea exciton by “Pauli scattering”, i.e., carrier… 
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Europhys. Lett
  • Europhys. Lett
  • 2002