Electric field enhancement of gold tip optical antenna with special geometry

This paper provides a new design for a gold tip optical antenna based on a specific geometry, and then, the change of electric field enhancement for plane wave laser excitation with 400 to 700 nm in the vicinity of optical antenna are simulated. Progressions of geometry incorporate the change of period of circular grating from 200–300 nm, on the shaft of antenna. In addition, the distribution of enhancement of the electric field in a plane perpendicular to the shaft has been acquired. Finally, the optimal value for the maximum enhancement at the period of 208.843 nm is calculated.