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arXiv · 1210.1420

Biexciton state preparation in a quantum dot via adiabatic rapid passage: comparison between two control protocols and impact of phonon-induced dephasing

M. Glässl·A. Barth·K. Gawarecki·P. Machnikowski·M. D. Croitoru·S. Lüker·D. E. Reiter·T. Kuhn·V. M. Axt
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Abstract

We investigate theoretically under which conditions a stable and high-fidelity preparation of the biexciton state in a quantum dot can be realized by means of adiabatic rapid passage in the presence of acoustic phonon coupling. Our analysis is based on a numerically complete real-time path integral approach and comprises different schemes of optical driving using frequency-swept (chirped) pulses. We show that depending on the size of the biexciton binding energy, resonant two-photon excitations or two-color schemes can be favorable. It is demonstrated that the carrier-phonon interaction strongly affects the efficiency of the protocols and that a robust preparation of the biexciton is restricted to positive chirps and low temperatures. A considerable increase of the biexciton yield can be achieved realizing temperatures below 4 K.

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M. Glässl, A. Barth, K. Gawarecki, P. Machnikowski, M. D. Croitoru, S. Lüker, D. E. Reiter, T. Kuhn, V. M. Axt. 2012-10-04. Biexciton state preparation in a quantum dot via adiabatic rapid passage: comparison between two control protocols and impact of phonon-induced dephasing. https://doi.org/10.1103/physrevb.87.085303

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