Dresden 2011 – wissenschaftliches Programm

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HL: Fachverband Halbleiterphysik

HL 70: Quantum Dots and Wires: Theory

HL 70.7: Vortrag

Donnerstag, 17. März 2011, 11:45–12:00, POT 151

Carrier multiplication in quantum dots: Quantum optical emission dynamics — •Franz Schulze, Sandra Cecilia Kuhn, Andreas Knorr, and Carsten Weber — Institut f. Theoretische Physik, Technische Universität Berlin, Germany

Measurements of carrier multiplication in quantum dots based on excitonic and multiexcitonic decay dynamics [1] show potential for its utilization in photovoltaic conversion, but also contradicting results. Theoretical treatments of the process are typically based on stationary methods or simple Bloch equation approaches [2]. As a more fundamental approach to an unambiguous signal of carrier multiplication, we present a microscopically derived dynamical model of carrier multiplication in a single quantum dot. Within this model a time resolved quantum optical emission spectrum is investigated, which shows a behaviour characteristic of the carrier multiplication dynamics observed in the purely electronic system. Different paths in the electronic system leading from an initial optical excitation to the creation of multiple carriers are discussed.
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