Borri, Paola  ORCID: https://orcid.org/0000-0002-7873-3314, Langbein, Wolfgang Werner ORCID: https://orcid.org/0000-0001-9786-1023, Woggon, U., Stavarache, V., Reuter, D. and Wieck, A. D.
2005.
Exciton dephasing via phonon interactions in InAs quantum dots: dependence on quantum confinement.
Physical Review B: Condensed Matter and Materials Physics
71
(11)
, 115328.
10.1103/PhysRevB.71.115328
|
Preview |
PDF
Download (89kB) | Preview |
Abstract
We report systematic measurements of the dephasing of the excitonic ground-state transition in a series of InGaAs?GaAs quantum dots having different quantum confinement potentials. Using a highly sensitive four-wave mixing technique, we measure the polarization decay in the temperature range from 5 to 120 K on nine samples having the energy distance from the dot ground-state transition to the wetting layer continuum (confinement energy) tuned from 332 to 69 meV by thermal annealing. The width and the weight of the zero-phonon line in the homogeneous line shape are inferred from the measured polarization decay and are discussed within the framework of recent theoretical models of the exciton-acoustic phonon interaction in quantum dots. The weight of the zero-phonon line is found to decrease with increasing lattice temperature and confinement energy, consistently with theoretical predictions by the independent Boson model. The temperature-dependent width of the zero-phonon line is well reproduced by a thermally activated behavior having two constant activation energies of 6 and 28 meV, independent of confinement energy. Only the coefficient to the 6-meV activation energy shows a systematic increase with increasing confinement energy. These findings rule out that the process of one-phonon absorption from the excitonic ground state into higher energy states is the underlying dephasing mechanism.
| Item Type: | Article |
|---|---|
| Date Type: | Publication |
| Status: | Published |
| Schools: | Schools > Biosciences Schools > Physics and Astronomy |
| Subjects: | Q Science > QC Physics |
| Publisher: | American Physical Society |
| ISSN: | 1098-0121 |
| Last Modified: | 10 May 2023 20:34 |
| URI: | https://orca.cardiff.ac.uk/id/eprint/1541 |
Citation Data
Cited 142 times in Scopus. View in Scopus. Powered By Scopus® Data
Actions (repository staff only)
 |
Edit Item |
Dimensions
Dimensions