Excitation and Guiding of Surface Plasmon Polariton in Metal/Insulator/Metal Structure on Glass Surface

Abstract

Appropriate illumination condition of polarized light at visible region might be absorbed and converted into metal/insulator/metal structure constructed with subwavelength thin films, especially gold or silver layers as metal filmes. The absorbed electromagnetic energy could be trasnferred into periodic fluctuation of free electron density in metal films, and resultant surface plasmon polariton could be excited at metal/insulator interface efficiently. This research aims for application of the SPP to intense and focused point light source as a optical fiber probe of scanning optical microscope. Basic characteristics of excitation and propagation of the SPP around dividing wall between twin-hole at one of the metal films have been studied both numerically and experimentally. The numerical simulations have been performed by commercial electromagnetic analysis package based on finite element method. On the other hand,the basic experiments have been done with both vacuum evaporated MIM structure on glass slide and focused ion beam fabrication method.