Applications of the surface plasmon polariton in the Au nanocircuit

We report the applications of surface plasmon polaritons (SPPs) in an optical nanocircuit of an Au nanoridge. Enhancement and radiations of the nanoantenna pair is investigated when they are fabricated at the incident end of the Au nanoridge. The coupling phenomenon is observed by using total internal reflection fluorescence microscopy (TIRFM) and is simulated by using a finite-difference time-domain (FDTD) method. The result shows that the enhanced field of the nanoantennas can be effectively coupled into the Au nanoridge when the incident angle is on the critical point and the length of the Au nanoridge is matched to the resonance frequency of the nanoantenna pair.