Molecular optomechanics in the anharmonic cavity-QED regime using hybrid metal-dielectric cavity modes

TL;DR

This paper demonstrates a novel hybrid metal-dielectric cavity system that achieves strong molecular optomechanical coupling, enabling the exploration of quantum plasmonics and nonlinear optical effects at the single-molecule level.

Contribution

The work introduces a hybrid cavity design that combines plasmonic and dielectric modes to reach strong coupling in molecular optomechanics, surpassing previous limitations.

Findings

Achieved anharmonic emission lines in the strong coupling regime.

Demonstrated deep sub-wavelength plasmonic confinement with enhanced cavity lifetime.

Enabled new studies in quantum plasmonics and single-molecule Raman scattering.

Abstract

Using carefully designed hybrid metal-dielectric resonators, we study molecular optomechanics in the strong coupling regime ($g_{\rm }^2/\omega_m {>} \kappa$), which manifests in anharmonic emission lines in the sideband-resolved region of the cavity-emitted spectrum ($\kappa{<}\omega_m$). This nonlinear optomechanical strong coupling regime is enabled through a metal-dielectric cavity system that yields not only deep sub-wavelength plasmonic confinement, but also dielectric-like confinement times that are more than two orders of magnitude larger than those from typical localized plasmon modes. These hybrid metal-dielectric cavity modes enable one to study new avenues of quantum plasmonics for single molecule Raman scattering.