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arXiv · 1704.03792

Phonon-assisted dark exciton preparation in a quantum dot

Sebastian Lüker·Tilmann Kuhn·Doris E. Reiter
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Abstract

In semiconductor quantum dots the coupling to the environment, i.e. to phonons, plays a crucial role for optical state preparation. We analyze the phonon impact on two methods for a direct optical preparation of the dark exciton, which is enabled by a tilted magnetic field: the excitation with a chirped laser pulse and the excitation with a detuned pulse. Our study reveals that for both methods phonons either do not impede the proposed mechanism or are even useful by widening the parameter range where a dark state preparation is possible due to phonon-assisted dark exciton preparation. In view of the positive impact of phonons on the optical preparation the use of dark excitons in quantum dots becomes even more attractive.

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Sebastian Lüker, Tilmann Kuhn, Doris E. Reiter. 2017-04-12. Phonon-assisted dark exciton preparation in a quantum dot. https://doi.org/10.1103/physrevb.95.195305

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