Autor: |
O. Wind, V. Sperling, Ulrike Woggon, S.V. Bogdanov |
Rok vydání: |
1994 |
Předmět: |
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Zdroj: |
Journal of Crystal Growth. 138:976-980 |
ISSN: |
0022-0248 |
Popis: |
CdS quantum dots under weak confinement conditions embedded in a polyvinyl alcohol (PVA) polymer film have been studied in the presence of an external electrical field at different densities of photoexcited carriers. Applying an external electric field strength of 5 × 104 V/cm, the observed absorption change δα/α in this material is ≈ 7%. At high laser excitation the electric field separates the laser excited carriers and the change in absorption is attributed to a compensation of the many-particle interaction by the external electrical field. A restoring of the oscillator strength is observed and explained by screening effects of the polarization fields in the interface region due to the photogenerated electron-hole pairs. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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