An Efficient and Compact Excitation of Surface Plasmons Using a Si Gable Tip

We propose a novel technique to efficiently excite a surface plasmon polariton (SPP) mode at a gold-glass interface by exploiting the near field excitation of an engineered high index (silicon) gabled tip at the telecom wavelengths. The proposed structure can theoretically convert 49% of the input optical power to a SPP mode. The device is compact, it will facilitate the on-chip excitation of the SPP, its fabrication is compatible with the standard Si fabrication processes, and as such, it is expected to be useful in the design of future integrated sensors.