Tuesday, 19 March, 2013
Confinement and Interaction of Single Indirect Excitons in a Voltage-Controlled Trap Formed Inside Double InGaAs Quantum Wells
G. Schinner, J. Repp, E. Schubert, A. Rai, D. Reuter, A. Wieck, A. Govorov, A. Holleitner, and J. Kotthaus -
Phys. Rev. Lett., Vol. 110 (12), 127403 (2013)
Voltage-tunable quantum traps confining individual spatially indirect and long-living excitons are realized by providing a coupled double quantum well with nanoscale gates. This enables us to study the transition from confined multiexcitons down to a single, electrostatically trapped indirect exciton. In the few exciton regime, we observe discrete emission lines identified as resulting from a single dipolar exciton, a biexciton, and a triexciton, respectively. Their energetic splitting is well described by Wigner-like molecular structures reflecting the interplay of dipolar interexcitonic repulsion and spatial quantization.