Dresden 2017 – wissenschaftliches Programm

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HL: Fachverband Halbleiterphysik

HL 63: Poster: Quantum Dots and Optics

HL 63.67: Poster

Mittwoch, 22. März 2017, 15:00–19:00, P1A

Numerical Investigation of the Nonlinear Optical Properties of Quantum Dot Molecules (QDM) — •Peter Kölling and Jens Förstner — Universität Paderborn, Germany

We theoretically study the optical properties of epitaxially grown InAs quantum dot molecules which are integrated in Schottky diode struc- tures. From optical experiments one knows that the electronic states inside the single quantum dots are coupled [1]. Applying gate voltages at these diode structures allows manipulation of the relative energies inside the single quantum dots as well as manipulation of carrier tun- neling between the dots [2,3]. This in turn can be used to achieve switching between electronic states at nano- or picosecond time scales. Nonlinearities arise due to the excitation of exciton complexes with variable numbers of electrons and holes.

We investigate single particle eigenenergies and eigenstates under the influence of an external electric field by means of k.p-theory with the nextnano3 software package [4]. From the resulting single particle eigenstates we calculate Coulomb matrix elements and optical matrix elements required for Heisenberg equations of motion for a reduced density operator of the underlying system. The Heisenberg equations of motion are then solved to calculate theoretical nonlinear absorption spectra.

0mm [1] G. Ordner et al., Phys. Rev. Lett. 94, 157401 (2006)
E. A. Stinaff et al., Science 311, 636-639 (2006)
M. Schreibner et al., Solid State Comm. 149, 1427-1435 (2009)
http://www.nextnano.de/nextnano3/