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Physical Review Letters

Control of Vertically Coupled InGaAs/GaAs Quantum Dots with Electric Fields

G. Ortner, M. Bayer, Yuli B. Lyanda-Geller, T. L. Reinecke, A. Kress, J.P. Reithmaier, A. Forchel

Published Apr 19, 2005• 146 citations
Publisher

Abstract

Controllable interactions that couple quantum dots are a key requirement in the search for scalable solid state implementations for quantum information technology. From optical studies of excitons and corresponding calculations, we demonstrate that an electric field on vertically coupled pairs of In(0.6)Ga(0.4)As/GaAs quantum dots controls the mixing of the exciton states on the two dots and also provides controllable coupling between carriers in the dots.

DOI
10.1103/physrevlett.94.157401

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Controllable interactions that couple quantum dots are a key requirement in the search for scalable solid state implementations for quantum information technology. From optical studies of excitons and corresponding calculations, we demonstrate that an electric field on vertically coupled pairs of In(0.6)Ga(0.4)As/GaAs quantum dots controls the mixing of the exciton states on the two dots and also provides controllable coupling between carriers in the dots.
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