Effect of lattice geometry on optical transmission through subwavelength nanohole arrays

We theoretically investigate refractive index sensors that are based on extraordinary optical transmission trough plasmonic nanoholes arranged in square and hexagonal lattices. The hexagonal system supports narrower spectral response and larger figure-of-merit values. Due its strong sensitivities, the hexagonal lattice also exhibits larger spectral shifts caused by a thin dielectric film which covers the aperture surface, mimicking a biomolecular layer.