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Updated: Jun 1, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Reversible switching of ultrastrong light-molecule coupling
T Schwartz1, J A Hutchison, C Genet
1ISIS, Université de Strasbourg and CNRS (UMR 7006), 8 allée Gaspard Monge, 67000, Strasbourg, France.
Abstract:
We demonstrate that photochromic molecules enable switching from the weak- to ultrastrong-coupling regime reversibly, by using all-optical control. This switch is achieved by photochemically inducing conformational changes in the molecule. Remarkably, a Rabi splitting of 700 meV is measured at room temperature, corresponding to 32% of the molecular transition energy. A similar coupling strength is demonstrated in a plasmonic structure. Such systems present a unique combination of coupling strength and functional capacities.
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