Collective Fluorescence of Graphene Quantum Dots on a surface

Hugo Levy-Falk; Suman Sarkar; Thanh Trung Huynh; Daniel Medina-Lopez; Lauren Hurley; Océane Capelle; Muriel Bouttemy; Gaëlle Trippé-Allard; Stéphane Campidelli; Loïc Rondin; Elsa Cassette; Emmanuelle Deleporte; Jean-Sébastien Lauret

arXiv · 2507.22458

Collective Fluorescence of Graphene Quantum Dots on a surface

Hugo Levy-Falk·Suman Sarkar·Thanh Trung Huynh·Daniel Medina-Lopez·Lauren Hurley·Océane Capelle·Muriel Bouttemy·Gaëlle Trippé-Allard·Stéphane Campidelli·Loïc Rondin·Elsa Cassette·Emmanuelle Deleporte·Jean-Sébastien Lauret

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Abstract

This study explores the organization of graphene quantum dots on the surface of monocrystalline halide perovskite. We show that graphene quantum dots tends to aggregate on the surface of perovskite unlike in solution or on other substrates, even at very low concentration of the initial solution that should yield single-molecule samples. Spectral analysis on small clusters shows a back-and-forth dynamical transition between an uncoupled, monomer-like state, and an excimer state. Following this "dance" between states, a drastic one-way increase in fluorescence intensity combined with a shortening of the excited state lifetime has been observed on some clusters. This behavior is related to the emission of a collective state that may be a consequence of the dynamical organization of graphene quantum dots under illumination on the surface of the perovksite.

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Hugo Levy-Falk, Suman Sarkar, Thanh Trung Huynh, Daniel Medina-Lopez, Lauren Hurley, Océane Capelle, Muriel Bouttemy, Gaëlle Trippé-Allard, Stéphane Campidelli, Loïc Rondin, Elsa Cassette, Emmanuelle Deleporte, Jean-Sébastien Lauret. 2025-10-30. Collective Fluorescence of Graphene Quantum Dots on a surface. https://arxiv.org/abs/2507.22458

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