Direct measurement of exciton diffusion in quantum wells
| Autor: | W. Heller, A. Filoramo, Ph. Roussignol, U. Bockelmann |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Photoluminescence
Condensed matter physics Liquid helium Chemistry Exciton Condensed Matter Physics Laser Fick's laws of diffusion Molecular physics Electronic Optical and Magnetic Materials law.invention law Materials Chemistry Electrical and Electronic Engineering Diffusion (business) Spectroscopy Quantum well |
| Zdroj: | Solid-State Electronics. 40:725-728 |
| ISSN: | 0038-1101 |
| DOI: | 10.1016/0038-1101(95)00351-7 |
| Popis: | We have measured the diffusion of excitons in GaAs quantum wells by using spatial and time-resolved photoluminescence (PL) spectroscopy at liquid helium temperature. A displacement of the detected region (O 1.5 μm) with respect to the laser spot allows us to monitor the lateral change of the PL time-dependence. With increasing displacement the maximum of the PL-intensity shifts systematically to later times. For a theoretical description an in-plane diffusion model is applied, with the diffusion constant D as the only fit parameter. We obtain a continuous increase of D from 15 cm2s−1 to 80 cm2s−1 for displacements from 0 to 4.2 μm. A measurement with only spatial resolution leads to a diffusion constant of 20 cm2s−1. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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