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arXiv · 2504.13657

Single-molecule electroluminescence: crossover from weak to strong coupling

Andrés Bejarano·Moritz Frankerl·Rémi Avriller·Thomas Frederiksen·Fabio Pistolesi
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Abstract

We develop a microscopic model to investigate current-induced light emission in single-molecule tunnel junctions, where a two-level system interacts with a plasmonic field. Using the quantum master equation, we explore the transition from weak to strong plasmon-molecule coupling, identifying three distinct regimes governed by cooperativity, which quantifies the interplay between interaction strength and losses. Our findings establish a framework to detect strong coupling, unveiling resonance-dependent features in the emission spectrum and photon correlations.

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Andrés Bejarano, Moritz Frankerl, Rémi Avriller, Thomas Frederiksen, Fabio Pistolesi. 2025-04-18. Single-molecule electroluminescence: crossover from weak to strong coupling. https://arxiv.org/abs/2504.13657

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