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arXiv · 1409.0913

Phonon-assisted population inversion of a single quantum dot

J. H. Quilter·A. J. Brash·F. Liu·M. Glässl·A. M. Barth·V. M. Axt·A. J. Ramsay·M. S. Skolnick·A. M. Fox
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Abstract

We demonstrate an approach to realize the population inversion of a single InGaAs/GaAs quantum dot, which is driven by a laser pulse tuned within the neutral exciton phonon sideband. The inversion is achieved by rapid thermalization of the optically dressed states via phonon-assisted relaxation. A maximum exciton population of 0.67 $\pm$ 0.06 is measured for a laser tuned 0.83 meV to higher energy and the phonon sideband is mapped using a two-color pump-probe technique. Our experiments reveal that, in accordance with theory, the phonon-bath provides additional functionality for an optically driven quantum dot qubit.

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J. H. Quilter, A. J. Brash, F. Liu, M. Glässl, A. M. Barth, V. M. Axt, A. J. Ramsay, M. S. Skolnick, A. M. Fox. 2014-09-02. Phonon-assisted population inversion of a single quantum dot. https://arxiv.org/abs/1409.0913

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