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Absorption and photoluminescence spectroscopy on a single self-assembled charge-tunable quantum dot

S. Seidl·M. Kroner·P. A. Dalgarno·A. Högele·J. M. Smith·M. Ediger·B. D. Gerardot·J. M. Garcia·P. M. Petroff·K. Karrai·R. J. Warburton
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Abstract

We have performed detailed photoluminescence (PL) and absorption spectroscopy on the same single self-assembled quantum dot in a charge-tunable device. The transition from neutral to charged exciton in the PL occurs at a more negative voltage than the corresponding transition in absorption. We have developed a model of the Coulomb blockade to account for this observation. At large negative bias, the absorption broadens as a result of electron and hole tunneling. We observe resonant features in this regime whenever the quantum dot hole level is resonant with two-dimensional hole states located at the capping layer-blocking barrier interface in our structure.

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S. Seidl, M. Kroner, P. A. Dalgarno, A. Högele, J. M. Smith, M. Ediger, B. D. Gerardot, J. M. Garcia, P. M. Petroff, K. Karrai, R. J. Warburton. 2005-10-27. Absorption and photoluminescence spectroscopy on a single self-assembled charge-tunable quantum dot. https://doi.org/10.1103/physrevb.72.195339

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