Twin Polaritons: Classical versus Quantum Features in Polaritonic Spectra
Phys. Rev. Lett. 135, 233601 – Published 1 December, 2025
DOI: https://doi.org/10.1103/32bq-tgr1
Abstract
Understanding whether a polaritonic phenomenon is fundamentally quantum or classical is essential for building accurate theoretical models and guiding experimental design. Here, we address this question in the context of polaritonic spectra and report an intriguing new feature: the twin polariton, an additional splitting beyond the primary resonant polariton splitting originating from vacuum field fluctuations. We show that the twin polariton persists in the many-molecule limit under permutationally symmetrical initial-state constraint and that it follows the same linear dependence on coupling strength as the primary polariton splitting. This establishes a novel mechanism by which a quantum feature (the twin polariton) can be tuned through a classical one (the primary polariton), offering new opportunities to probe and control the fundamental nature of polaritonic systems.
Physics Subject Headings (PhySH)
- Classical optics
- Light-matter interaction
- Molecular spectra
- Photonics
- Quantum optics
- Rotational states
- Strong electromagnetic field effects
- Vibrational states
- Microcavity & microdisk lasers
- Molecules
- Quantum cavities
- First-principles calculations
- Quantum chemistry methods
- Schroedinger equation
- Semiclassical methods
Corrections
7 July, 2026
Correction: The omission of a statement of thanks in the Acknowledgments section has been rectified.