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arXiv · 1602.00628

Ultrafast Depopulation of a Quantum Dot by LA-phonon-assisted Stimulated Emission

F. Liu·L. M. P. Martins·A. J. Brash·A. M. Barth·J. H. Quilter·V. M. Axt·M. S. Skolnick·A. M. Fox
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Abstract

We demonstrate ultrafast incoherent depopulation of a quantum dot from above to below the transparency point using LA-phonon-assisted emission stimulated by a redshifted laser pulse. The QD is turned from a weakly vibronic system into a strongly vibronic one by laser driving which enables the phonon-assisted relaxation between the excitonic components of two dressed states. The depopulation is achieved within a laser pulse-width-limited time of 20 ps and exhibits a broad tuning range of a few meV. Our experimental results are well reproduced by path-integral calculations.

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F. Liu, L. M. P. Martins, A. J. Brash, A. M. Barth, J. H. Quilter, V. M. Axt, M. S. Skolnick, A. M. Fox. 2016-02-01. Ultrafast Depopulation of a Quantum Dot by LA-phonon-assisted Stimulated Emission. https://doi.org/10.1103/physrevb.93.161407

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