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arXiv · 0801.0364

Optical control of energy-level structure of few electrons in AlGaAs/GaAs quantum dots

Sokratis Kalliakos·Vittorio Pellegrini·Cesar Pascual Garcia·Aron Pinczuk·Loren N. Pfeiffer·Ken. W. West
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Abstract

Optical control of the lateral quantum confinement and number of electrons confined in nanofabricated GaAs/AlGaAs quantum dots is achieved by illumination with a weak laser beam that is absorbed in the AlGaAs barrier. Precise tuning of energy-level structure and electron population is demonstrated by monitoring the low-lying transitions of the electrons from the lowest quantum-dot energy shells by resonant inelastic light scattering. These findings open the way to the manipulation of single electrons in these quantum dots without the need of external metallic gates.

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Sokratis Kalliakos, Vittorio Pellegrini, Cesar Pascual Garcia, Aron Pinczuk, Loren N. Pfeiffer, Ken. W. West. 2008-01-02. Optical control of energy-level structure of few electrons in AlGaAs/GaAs quantum dots. https://doi.org/10.1021/nl072904p

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