High-resolution 2D plasmonic fan-out realized by subwavelength slit arrays

The authors demonstrate a two dimensional (2D) plasmonic fan-out spot array by using subwavelength sized slit arrays. Near field scanning optical microscope (NSOM) is employed to examine intensity distributions of the generated fan-out plasmonic spots, showing good agreement with finite-difference time-domain (FDTD) simulation results. The plasmonic fan-out spots with full width half-maximum (FWHM) of 0.34 lambda(0) are optimized by various design parameters associated with the subwavelength slit as well as polarization states.