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Updated: Jul 16, 2026

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Fine structure of negatively and positively charged excitons in semiconductor quantum dots: electron-hole asymmetry
M Ediger1, G Bester, B D Gerardot
1School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom.
Abstract:
We present new understanding of excitonic fine structure in close-to-symmetric InAs/GaAs and InGaAs/GaAs quantum dots. We demonstrate excellent agreement between spectroscopy and many-body pseudopotential theory in the energy splittings, selection rules and polarizations of the optical emissions from doubly charged excitons. We discover a marked difference between the fine structure of the doubly negatively and doubly positively charged excitons. The features in the doubly charged emission spectra are shown to arise mainly from the lack of inversion symmetry in the underlying crystal lattice.
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