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arXiv · 0711.4205

Observation of dressed excitonic states in a single quantum dot

Gregor Jundt·Lucio Robledo·Alexander Högele·Stefan Fält·Atac Imamoğlu
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Abstract

We report the observation of dressed states of a quantum dot. The optically excited exciton and biexciton states of the quantum dot are coupled by a strong laser field and the resulting spectral signatures are measured using differential transmission of a probe field. We demonstrate that the anisotropic electron-hole exchange interaction induced splitting between the x- and y-polarized excitonic states can be completely erased by using the AC-Stark effect induced by the coupling field, without causing any appreciable broadening of the spectral lines. We also show that by varying the polarization and strength of a resonant coupling field, we can effectively change the polarization-axis of the quantum dot.

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Gregor Jundt, Lucio Robledo, Alexander Högele, Stefan Fält, Atac Imamoğlu. 2007-11-27. Observation of dressed excitonic states in a single quantum dot. https://doi.org/10.1103/physrevlett.100.177401

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