Nanocavities for Molecular Optomechanics: their fundamental description and applications

Abstract

Vibrational Raman scattering -- a process where light exchanges energy with a molecular vibration through inelastic scattering -- is most fundamentally described in a quantum framework where both light and vibration are quantized. When the Raman scatterer is embedded inside a plasmonic nanocavity, as in some sufficiently controlled implementations of surface-enhanced Raman scattering (SERS), the coupled system realizes an optomechanical cavity, where coherent and parametrically amplified light-vibration interaction becomes a resource for vibrational state engineering and nanoscale nonlinear optics. The purpose of this Perspective is to clarify the connection between the languages and parameters used in the fields of molecular cavity optomechanics (McOM) vs. its conventional, `macroscopic' counterpart, and to summarize the main results achieved so far in McOM and the most pressing experimental and theoretical challenges. We aim to make the theoretical framework of molecular cavity optomechanics practically usable for the SERS and nanoplasmonics community at large. While quality factors ($Q$'s) and mode volumes ($V$'s) essentially describe the performance of a nanocavity in enhancing light-matter interaction, we point to the light-cavity coupling efficiencies ($\eta$'s) and optomechanical cooperativities ($\mathcal{C}$'s) as the key parameters for molecular optomechanics. As an illustration of the significance of these quantities, we investigate the feasibility of observing optomechanically induced transparency with a molecular vibration -- a measurement that would allow for a direct estimate of the optomechanical cooperativity.

Includes an Appendix

References in corpus (47)

• Cavity Optomechanics
• Laser cooling of a nanomechanical oscillator into its quantum ground state
• Optomechanically induced transparency
• Electromagnetically Induced Transparency and Slow Light with Optomechanics
• Quantum-coherent coupling of a mechanical oscillator to an optical cavity mode
• Circuit cavity electromechanics in the strong coupling regime
• The photon blockade effect in optomechanical systems
• Single-photon Optomechanics
• On the use of Purcell factors for plasmon antennas
• Measurement and control of a mechanical oscillator at its thermal decoherence rate
• Molecular cavity optomechanics: a theory of plasmon-enhanced Raman scattering
• Perfect Reflection of Light by an Oscillating Dipole
• Nanomechanical Resonators: Toward Atomic Scale
• QED description of Raman scattering from molecules in plasmonic cavities
• Near-to-far field transformations for radiative and guided waves
• Detecting mid-infrared light by molecular frequency upconversion with dual-wavelength hybrid nanoantennas
• Dissipative and Dispersive Optomechanics in a Nanocavity Torque Sensor
• Continuous-Wave Frequency Upconversion with a Molecular Optomechanical Nanocavity
• Antenna-cavity hybrids: matching polar opposites for Purcell enhancements at any linewidth
• Transformation Optics Approach to Plasmon-Exciton Strong Coupling in Nanocavities
• Approaching the motional ground state of a 10 kg object
• Laser cooling of a nanomechanical oscillator to the zero-point energy
• Quantum limit of laser cooling in dispersively- and dissipatively-coupled optomechanical systems
• Langevin Approach to Quantum Optics with Molecules
• Quantum Optics Model of Surface Enhanced Raman Spectroscopy for Arbitrarily Shaped Plasmonic Resonators
• Two-Color Pump-Probe Measurement of Photonic Quantum Correlations Mediated by a Single Phonon
• Giant optomechanical spring effect in plasmonic nano- and picocavities probed by surface-enhanced Raman scattering
• Extraction of the beta-factor for single quantum dots coupled to a photonic crystal waveguide
• Power dependence of Klyshko's Stokes-anti-Stokes correlation in the inelastic scattering of light
• Intrinsic Luminescence Blinking from Plasmonic Nanojunctions
• Quasinormal-mode perturbation theory for dissipative and dispersive optomechanics
• Light emission in nanogaps: overcoming quenching
• Photonic Counterparts of Cooper Pairs
• Bright Optical Eigenmode with about 1 nm ${}^3$ Volume
• Reproducible Ultrahigh Electromagnetic SERS Enhancement in Nanosphere-Plane Junctions
• Quantum backaction and noise interference in asymmetric two-cavity optomechanical systems
• Molecular platform for frequency upconversion at the single-photon level
• An integrated diamond Raman laser pumped in the near-visible
• Plasmonic Purcell Effect in Organic Molecules
• Hybrid cavity-antenna architecture for strong and tunable sideband-selective molecular Raman scattering enhancement
• Resonant Raman scattering of single molecules under strong cavity coupling and ultrastrong optomechanical coupling in plasmonic resonators: phonon-dressed polaritons
• Structural Order of the Molecular Adlayer Impacts the Stability of Nanoparticle-on-Mirror Plasmonic Cavities
• Measurement-Induced Collective Vibrational Quantum Coherence under Spontaneous Raman Scattering in a Liquid
• Semi-empirical Quantum Optics for Mid-Infrared Molecular Nanophotonics
• Ultrafast Response of Plasmonic Nanostructures
• On the Excitation and Radiative Decay Rates of Plasmonic Nanoantennas
• Mode-specific Coupling of Nanoparticle-on-Mirror Cavities with Cylindrical Vector Beams

Cited by in corpus (6)

• Nonreciprocal entanglement in a molecular optomechanical system
• Photon Antibunching in Single-Molecule Vibrational Sum-Frequency Generation
• Plasmonic Nanoparticle-in-nanoslit Antenna as Independently Tunable Dual-Resonant Systems for Efficient Frequency Upconversion
• Enhancing mechanical entanglement in molecular optomechanics
• Rigorous electromagnetic quasinormal-mode method made easy for users
• Continuous-wave, high-resolution, ultra-broadband mid-infrared nonlinear spectroscopy with tunable plasmonic nanocavities