Surface-enhanced plasmon splitting in a liquid-crystal-coated gold nanoparticle

Area of Science:

• Plasmonics
• Soft Matter Physics
• Nanotechnology

Background:

• Gold nanoparticles exhibit unique optical properties due to surface plasmon resonance.
• Liquid crystals possess anisotropic properties that can influence nanoparticle behavior.
• Surface plasmon splitting is a phenomenon sensitive to the local dielectric environment.

Purpose of the Study:

• To investigate the effect of liquid crystal coatings on the surface plasmon splitting of gold nanoparticles.
• To explore different liquid crystal director configurations and their impact on plasmonics.
• To correlate theoretical predictions with experimental observations.

Main Methods:

• Utilizing the discrete dipole approximation (DDA) to model optical properties.
• Simulating gold nanoparticles coated with nematic liquid crystals.
• Analyzing three director configurations: boojum pair, baseball, and homogeneous.

Main Results:

• The nanoparticle surface strongly influences liquid crystal director orientation.
• Liquid crystal deformation surprisingly enhances surface plasmon splitting.
• The boojum pair configuration yielded the largest surface plasmon splitting.

Conclusions:

• The interaction between gold nanoparticles and liquid crystals can be leveraged to tune plasmonic properties.
• The director configuration of the liquid crystal layer is critical for optimizing surface plasmon splitting.
• Theoretical predictions using DDA are in good agreement with experimental results.