Multimode Phonon-Polaritons in Lead-Halide Perovskites in the Ultrastrong Coupling Regime

Abstract

Phonons play a central role in fundamental solid-state phenomena, including superconductivity, Raman scattering, and symmetry-breaking phases. Harnessing phonons to control these effects and enable quantum technologies is therefore of great interest. However, most existing phonon control strategies rely on external driving fields or anharmonic interactions, limiting their applicability. Here, we realize multimode ultrastrong light--matter coupling and theoretically show the modulation of phonon emission. This regime is realized by coupling two optical phonon modes in lead halide perovskites to a nanoslot array functioning as a single-mode cavity. The small mode volume of the nanoslots enables high coupling strengths in the phonon-polariton system. We show theoretically that the nanoslot resonator mediates an effective interaction between phonon modes, leading to superthermal phonon bunching in thermal equilibrium between distinct modes. Our findings are well described by a multimode Hopfield model. This work establishes a pathway for engineering phononic properties for light-harvesting and light-emitting technologies.

References in corpus (19)

• Terahertz-Field-Induced Ferroelectricity in Quantum Paraelectric SrTiO${}_3$
• Optical Phonons in Methylammonium Lead Halide Perovskites and Implications for Charge Transport
• Phonon-mediated quantum state transfer and remote qubit entanglement
• Ultrastrong Coupling in the Near-field of Complementary Split Ring Resonators
• Ultrastrong plasmon-phonon coupling via epsilon-near-zero nanocavities
• Nonclassical Radiation from Thermal Cavities in the Ultrastrong Coupling Regime
• Optical Tunneling through Arbitrarily-Shaped Plasmonic Channels and Sharp Bends
• Developing a platform for linear mechanical quantum computing
• Ultrastrong Magnon-Magnon Coupling Dominated by Antiresonant Interactions
• Squeezing and multimode entanglement of surface acoustic wave phonons
• On-chip distribution of quantum information using traveling phonons
• Coupling and Decoupling of Polaritonic States in Multimode Cavities
• Observation of the Magnonic Dicke Superradiant Phase Transition
• Ultrafast spontaneous spin switching in an antiferromagnet
• Perspective on real-space nanophotonic field manipulation using non-perturbative light-matter coupling
• Controlling the electro-optic response of a semiconducting perovskite coupled to a phonon-resonant cavity
• Multimode Ultrastrong Coupling in Three-Dimensional Photonic-Crystal Cavities
• Signatures of Mode-Resolved, Nonlocal Electron-Phonon Coupling in Two-Dimensional Spectroscopy
• Phonon Signatures in Photon Correlations