Design and analysis of an all optical OR gate using surface plasmon hopping along metallic nanorods

This paper proposes a novel design technique for realization of plasmonic logic gates. A 2D plasmonic all optical OR gate with the miniaturized size of 5 μm × 3 μm is presented. Ag metallic reflectors form the input and output waveguides to confine the light inside the gate. The logic operations are realized through selective propagation of light in the gate through hopping of the surface plasmon resonances along the metallic nanorods. With this novel idea approximately 100% of input signal propagates through the output waveguide and no division occurs at the cross point. Due to its simplicity, the OR gate was chosen to be the first implemented logic gate to verify the performance of the proposed method. Our proposed optical gate works at the operating wavelength of 652 nm with input signals of a transverse magnetic (TM) (H_z, E_x, E_y) polarized continuous wave with near zero cross talk between two input waveguides. (paper)