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arXiv · 2607.09419

Coherent dynamics of individual excitons in a quantum dot embedded in a nanopost

Maxime Gaignard·Karolina Ewa Polczynska·Niels Gregersen·Daniel Wigger·Jean-Philippe Poizat·Jean-Michel Gérard·Julien Claudon·Jacek Kasprzak
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Abstract

We measured coherent ultrafast dynamics of exciton complexes in a single strongly-confined InAs quantum dot embedded in a GaAs nanopost. Such a photonic structure combines a wave guiding with a cavity effect and assures an enhanced light-matter coupling. Coherence properties of an exciton-biexciton system hosted by a quantum dot are assessed with four-wave mixing microscopy. Our results show that this broad-band photonic structure is an excellent asset to probe coherent couplings in a small set of solid state quantum systems and to investigate the coherence dynamics within the level structure of their excited states.

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Maxime Gaignard, Karolina Ewa Polczynska, Niels Gregersen, Daniel Wigger, Jean-Philippe Poizat, Jean-Michel Gérard, Julien Claudon, Jacek Kasprzak. 2026-07-10. Coherent dynamics of individual excitons in a quantum dot embedded in a nanopost. https://arxiv.org/abs/2607.09419

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