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arXiv · 2108.13901

Organic charged polaritons in the ultrastrong coupling regime

Mao Wang·Suman Mallick·Anton Frisk Kockum·Karl Börjesson
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Abstract

We embedded an all-hydrocarbon-based carbocation in a metallic microcavity that was tuned to resonance with an electronic transition of the carbocation. The measured Rabi splitting was 41% of the excitation energy, putting the system well into the ultrastrong coupling regime. Importantly, due to the intrinsic charge on the carbocation, the polaritons that form carry a significant charge fraction $0.55 e_0$ and a large charge-to-mass ratio ($\sim 2400 e_0 / m_0$). Moreover, the ground state of the ultrastrongly coupled system is calculated to carry about one percent of one elementary charge, implying a potentially enhanced charge transport across the molecules. These unique properties of our system, together with its convenient preparation, provide a practical platform to study charged polaritons in the ultrastrong coupling regime.

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Mao Wang, Suman Mallick, Anton Frisk Kockum, Karl Börjesson. 2021-08-31. Organic charged polaritons in the ultrastrong coupling regime. https://doi.org/10.1103/physrevresearch.4.023016

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