POLARITON MOTIONAL NARROWING IN SEMICONDUCTOR MULTIPLE-QUANTUM WELLS

Citation
Jj. Baumberg et al., POLARITON MOTIONAL NARROWING IN SEMICONDUCTOR MULTIPLE-QUANTUM WELLS, Physical review letters, 80(16), 1998, pp. 3567-3570
Citations number
20
Categorie Soggetti
Physics
Journal title
ISSN journal
00319007
Volume
80
Issue
16
Year of publication
1998
Pages
3567 - 3570
Database
ISI
SICI code
0031-9007(1998)80:16<3567:PMNISM>2.0.ZU;2-P
Abstract
We demonstrate a new fast-scan ultrafast coherent reflectivity techniq ue that tracks the amplitude and phase of excitons in GaAs heterostruc tures at densities down to 4 x 10(6) cm(-2). Observed growth in the ex citon coherence over the first 1.5 ps is direct evidence for the prese nce of interfering polariton modes. Polariton theory provides a good a ccount of the data as the number of quantum wells is increased. Polari ton motional narrowing of spectral lines from multiple quantum wells i s demonstrated both experimentally and theoretically, annealing out th e inhomogeneous broadening of the exciton energies.