Simulation and Fabrication of Hybrid Optical Waveguide with a Sharp Bend Structure for High Integration

A hybrid optical waveguide having a 90° sharp bend structure, composed of a dielectric straight waveguide, tapered dielectric strip waveguide, and microscale metal gap waveguide, is experimentally demonstrated in an attempt to improve the efficiency of light coupling between dielectric and plasmonic waveguides. Due to both the efficient structure of the taper and metal gap, the calculated coupling efficiency reached as high as 63% in the fiber optic communication wavelength range. A dielectric-gold plasmonic waveguide was then fabricated, demonstrating a 17-dB coupling efficiency. Our experimental demonstration is a critical step for the hybrid integration of plasmonic components with conventional dielectric components