Surface-Enhanced Plasmon Splitting in a Liquid-Crystal-Coated Gold Nanoparticle

Abstract

We show that, when a gold nanoparticle is coated by a thin layer of nematic liquid crystal, the deformation produced by the nanoparticle surface can enhance the splitting of the nanoparticle surface plasmon. We consider three plausible liquid crystal director configurations in zero electric field: boojum pair (north-south pole configuration), baseball (tetrahedral), and homogeneous. From a calculation using the Discrete Dipole Approximation, we find that the surface plasmon splitting is largest for the boojum pair, intermediate for the homogeneous, and smallest for the baseball configuration. The boojum pair results are in good agreement with experiment. We conclude that the nanoparticle surface has a strong effect on the director orientation, but, surprisingly, that this deformation can actually enhance the surface plasmon splitting.

arXiv comment5 pages, 3 figures To be published in PRL

References in corpus (4)

• Topological Defects and Interactions in Nematic Emulsions
• Towards a Tetravalent Chemistry of Colloids
• Splitting of Surface Plasmon Frequencies of Metal Particles in a Nematic Liquid Crystal
• Structure Formation, Melting, and the Optical Properties of Gold/DNA Nanocomposites: Effects of Relaxation Time

Cited by in corpus (4)

• Boojums in Rotating Two-Component Bose-Einstein Condensates
• Electrically Controlled Plasmonic Lasing Resonances with Silver Nanoparticles Embedded in Amplifying Nematic Liquid Crystals
• Light scattering by a metallic nanoparticle coated with a nematic liquid crystal
• Plasmonic Waves on a Chain of Metallic Nanoparticles: Effects of a Liquid Crystalline Host or an Applied Magnetic Field