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arXiv · 1210.6096

Adiabatic rapid passage in quantum dots: phonon-assisted decoherence and biexciton generation

K. Gawarecki·S. Lüker·D. E. Reiter·T. Kuhn·M. Glässl·V. M. Axt·A. Grodecka-Grad·P. Machnikowski
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Abstract

We study the evolution of a quantum dot controlled by a frequency-swept (chirped), linearly polarized laser pulse in the presence of carrier-phonon coupling. The final occupation of the exciton state is limited both due to phonon-induced transitions between the adiabatic spectral branches and because of phonon-assisted transitions to the biexciton state. When the biexciton shift is large enough, the quantum dot can be modeled as a two-level system, which corresponds to excitation with circularly polarized light. For this case, we compare different methods of simulations: (i) a time convolutionless method, (ii) correlation expansion and (iii) path integrals. We show that results obtained from these methods agree perfectly at low temperatures.

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K. Gawarecki, S. Lüker, D. E. Reiter, T. Kuhn, M. Glässl, V. M. Axt, A. Grodecka-Grad, P. Machnikowski. 2012-10-23. Adiabatic rapid passage in quantum dots: phonon-assisted decoherence and biexciton generation. https://doi.org/10.1002/pssc.201200746

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