Strong optical coupling in metallo-dielectric hybrid metasurfaces

Area of Science:

• Nanophotonics
• Metamaterials
• Optics

Background:

• Hybrid metal/dielectric nanostructures offer unique optical properties.
• Metasurfaces combining materials can confine fields and reduce losses.
• Novel light-matter interactions are enabled by hybrid designs.

Purpose of the Study:

• To design and analyze a metallo-dielectric hybrid metasurface.
• To achieve strong coupling between anapole states and surface plasmon polaritons.
• To explore applications in open cavity strongly coupled optical systems.

Main Methods:

• Design of a hybrid metasurface with silicon nanodisks on an aluminum layer, separated by silica.
• Tuning nanodisk dimensions for anapole states and array period for surface plasmon polaritons.
• Finite difference time domain (FDTD) simulations to analyze mode coupling and optical properties.

Main Results:

• Excitation of anapole and surface plasmon polariton modes at normal incidence in the visible-NIR range.
• Strong coupling between anapole and surface plasmon polariton modes observed at a specific height (∼200 nm).
• Achieved a vacuum Rabi splitting of up to ∼129 meV through optimization.

Conclusions:

• The proposed hybrid metasurface demonstrates strong coupling between distinct optical modes.
• The design facilitates novel light-matter interactions and enhanced optical properties.
• This platform is promising for developing room-temperature, strongly coupled optical systems.