Double Slit Diffraction Experiment with Surface Plasmon Polaritons

Abstract

Surface Plasmon Polaritons (SPP) is a quasi two dimensional electromagnetic wave coupled with the free electrons in the metal. Most of the electric field and magnetic fields are contained in the dielectric. Since SPP is a wave, it should exhibit wave like behavior such as, interference, diffraction etc. Young’s double slit experiment is the most famous interference experiment. Two parallel waveguides were used for producing interference patterns with SPPs, which is equivalent to the Young’s double slit diffraction experiment. SPP interference was studied using SPP tomography. A series of experiments were done changing the separation of the waveguides. There was a good correspondence between observed and simulated interference patterns.