Electronic states of semiconductor clusters: Homogeneous and inhomogeneous broadening of the optical spectrum
- 1 October 1988
- journal article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 89 (7), 4001-4011
- https://doi.org/10.1063/1.454833
Abstract
The homogeneous (single-cluster) and inhomogeneous contributions to the low temperature electronic absorption spectrum of 35–50 Å diameter CdSe clusters are separated using transient photophysical hole burning. The clusters have the cubic bulk crystal structure, but their electronic states are strongly quantum confined. The inhomogeneous broadening of these features arises because the spectrum depends upon cluster size and shape, and the samples contain similar, but not identical, clusters. The homogeneous spectrum, which consists of a peak 140 cm−1 (17 meV) wide, with a phonon sideband and continuum absorption to higher energy, is compared to a simple molecular orbital model. Electron–vibration coupling, which is enhanced in small clusters, contributes to the substantial broadening of the homogeneous spectrum. The inhomogeneous width of the lowest allowed optical transition was found to be 940 cm−1, or seven times the homogeneous width, in the most monodisperse sample.Keywords
This publication has 17 references indexed in Scilit:
- Energy dependence of electronic relaxation processes in polyatomic moleculesPublished by Springer Science and Business Media LLC ,2007
- NMR Study of Semiconductor Molecular ClustersPhysical Review Letters, 1988
- Surface derivatization and isolation of semiconductor cluster moleculesJournal of the American Chemical Society, 1988
- Excitonic optical nonlinearity and exciton dynamics in semiconductor quantum dotsPhysical Review B, 1987
- Theory of the linear and nonlinear optical properties of semiconductor microcrystallitesPhysical Review B, 1987
- Transient photobleaching of small cadmium selenide colloids in acetonitrile. Anodic decompositionThe Journal of Physical Chemistry, 1987
- Quantum size effects in spherical semiconductor microcrystalsPhysical Review B, 1987
- Linear- and nonlinear-optical properties of free and bound excitons in CdS and applications in bistable devicesJournal of the Optical Society of America B, 1985
- Theory of the first-order Raman effect in crystalsProceedings of the Royal Society of London. Series A - Mathematical and Physical Sciences, 1963
- Deformation Potentials and Mobilities in Non-Polar CrystalsPhysical Review B, 1950