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Updated: Jun 8, 2026

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Correlated electrons in optically tunable quantum dots: building an electron dimer molecule
Achintya Singha1, Vittorio Pellegrini, Aron Pinczuk
1NEST, Istituto di Nanoscienze-CNR and Scuola Normale Superiore, Pisa 56127, Italy.
Abstract:
We observe the low-lying excitations of a molecular dimer formed by two electrons in a GaAs semiconductor quantum dot in which the number of confined electrons is tuned by optical illumination. By employing inelastic light scattering we identify the intershell excitations in the one-electron regime and the distinct spin and charge modes in the interacting few-body configuration. In the case of two electrons, a comparison with configuration-interaction calculations allows us to link the observed excitations with the breathing mode of the molecular dimer and to determine the singlet-triplet energy splitting.
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