Publication

Minimum of oscillator strength of excitons in ultra-narrow GaAs/AlGaAs quantum wells: Theory and experiment

Jean-Louis Staehli
1998
Journal Articles

Abstract

A theoretical and experimental study of the exciton in ultra-narrow quantum wells (QWs) is performed. A crossover from strong (separate localization of electron and hole levels) to weak confinement (with localization of excitonic center of mass) is predicted to occur for decreasing thickness, and is characterized by a minimum of the oscillator strength per unit area. Cathodoluminescence measurements performed on a series of GaAs/Al0.35Ga0.65As QWs with thicknesses from one to eight monolayers show a minimum of the oscillator strength, in agreement with theory, and indicate that the crossover from strong to weak confinement occurs at a thickness of about three monolayers for this composition. (C) 1998 Elsevier Science B.V. All rights reserved.

Official source

https://infoscience.epfl.ch/entities/publication/ea43358d-fffa-4983-ad43-1b9ad1b70300

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Jean-Louis Staehli
1998
Journal Articles

Abstract

Official source

https://infoscience.epfl.ch/entities/publication/ea43358d-fffa-4983-ad43-1b9ad1b70300

About this result

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