Parts | Days | Selection | Search | Downloads | Help
HL: Halbleiterphysik
HL 41: Quantenpunkte und -dr
ähte: Optische Eigenschaften II
HL 41.6: Talk
Thursday, March 27, 2003, 12:15–12:30, POT/81
Control of coupling of exciton states in quantum dot molecules by electric fields — •Gerhard Ortner1,2, M. Bayer1,2, A.F. Kress2, A.V. Larionov1,2, A. Forchel2, Yu. Lyanda-Geller3, T.L. Reinecke3, P. Hawrylak4, M. Korkusinski4, S. Fafard4, and Z. Wasilewski4 — 1Experimentelle Physik II, Otto-Hahn-Str. 4, 44221 — 2Technische Physik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany — 3Naval Research Laboratory, Washington DC, USA — 4Institute of Microstructual Science, National Research Council, Ottawa, Canada
Semiconductor Quantum Dots (QDs) are of
interest for potential application in quantum information
processing. An essential block of a quantum processor is a quantum
gate which entangles the states of two quantum bits.
A pair of
vertically aligned QDs has been suggested as promising candidate
for an optically driven quantum gate. Recently the coupling of the
exciton states in a single QD molecule has been revealed due to
tunneling of carriers in a QD molecule. Here we present
spectroscopic studies of single self-assembled
In0.60Ga0.40As/GaAs QD molecules, where the exciton
states have been manipulated by an electric field along the
heterostructure growth direction: tunneling of electron and hole
is prevented, and emission from direct and indirect excitons in
which electron and hole are located on the same or on opposite
QDs, respectively, is observed. These investigations have been
compared to calculations of the exciton emission energies and
oscillator strengths.