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Plasmonic modes confined to metallic nanostructures at the atomic and molecular scale push the boundaries of light–matter interactions. Within these extreme plasmonic structures of ultrathin nanogaps, coupled nanoparticles, and tunnelling junctions, new physical phenomena arise when plasmon resonances couple to electronic, exitonic, or vibrational excitations, as well as the efficient generation of non-radiative hot carriers. This review surveys the latest experimental and theoretical advances in the regime of extreme nano-plasmonics, with an emphasis on plasmon-induced hot carriers, strong coupling effects, and electrically driven processes at the molecular scale. We will also highlight related nanophotonic and optoelectronic applications including plasmon-enhanced molecular light sources, photocatalysis, photodetection, and strong coupling with low dimensional materials.
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This content will become publicly available on July 21, 2026
Collision-induced spectroscopy and radiative association in microcavities
Polariton chemistry has emerged as a new approach for directing molecular systems via strong light–matter interactions in confined photonic media. In this work, we implement a classical electrodynamics–molecular dynamics method to investigate collision-induced emission and radiative association in planar microcavities under variable light–matter coupling strength. We focus on the argon–xenon (Ar–Xe) gas mixture as a representative system, simulating collisions coupled to the confined multimode electromagnetic field. We find that while the effects of a microcavity on collision-induced emission spectra are subtle, even at extremely large coupling strengths, radiative association can be significantly enhanced in a microcavity. Our results also indicate that microcavities may be designed to induce changes in the statistical distribution of Ar–Xe complex lifetimes. These findings provide new insights into the control of intermolecular interactions and radiative kinetics with microcavities.
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- Award ID(s):
- 2340746
- PAR ID:
- 10650760
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 163
- Issue:
- 3
- ISSN:
- 0021-9606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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