Experiment demonstration of backward-propagating surface plasmon resonance mode

Abstract

Surface plasmon resonance (SPR) is the physical process of surface plasmon excitation. The polarization sensitivity of the coupling efficiency and control of the directionality of SPR are facing challenges. We have experimentally demonstrated a new plasmonic coupler that overcomes these challenges using nano scale particles on a silver film. Our device is based on the Mie scattering of SPR and achieves a complete bidirectional excitation. The proposed design can be used to create sensors with both bidirectional and unidirectional launching of SPR, and consequently, can be extended to a broad range of applications in biosensor systems.