Title: Single-exciton energy shell structure in InAs/GaAs quantum dots
Authors: Awirothananon, S.
Raymond, S.
Studenikin, S.
Vachon, M.
Render, W.
Sachrajda, A.
Wu, X.
Babinski, A.
Potemski, M.
Fafard, S.
Cheng, S. J.
Korkusinski, M.
Hawrylak, P.
Department of Electrophysics
Keywords: bound states;exchange interactions (electron);excited states;excitons;gallium arsenide;III-V semiconductors;indium compounds;magneto-optical effects;photoluminescence;semiconductor quantum dots;spectral line shift
Issue Date: 1-Dec-2008
Abstract: The energy shell structure of a single exciton confined in a self-assembled quantum dot (QD), including excited states, is studied in a regime where the direct Coulomb attraction energy is comparable to the kinetic energy of the carriers. This is achieved via magnetophotoluminescence excitation spectroscopy experiments, where a magnetic field applied perpendicular to the plane of the QD is used to reveal the angular-momentum content of energy shells. The absorption spectrum of the QDs is modeled, and comparison with experiment allows us to relate the observed transitions to interband QD bound-state transitions. The blueshift of the absorption peaks compared to the emission peaks is then interpreted in terms of many-body interactions, and we show that for a highly symmetric situation, the observed energy difference gives a direct measurement of the extra exchange energy gained upon addition of an extra exciton in the QD.
URI: http://dx.doi.org/10.1103/PhysRevB.78.235313
ISSN: 1098-0121
DOI: 10.1103/PhysRevB.78.235313
Volume: 78
Issue: 23
End Page: 
Appears in Collections:Articles