Efficient light coupling between dielectric slot waveguide and plasmonic slot waveguide

摘要

An efficient coupler between a dielectric waveguide and a plasmonic metal–insulator–metal (MIM) waveguide is proposed, modeled, fabricated, and characterized. Based on the platform of a silicon slot waveguide, a quasi-MIM plasmonic junction is formed via e-beam lithography and lift-off process. Coupling efficiency between the silicon slot waveguide and plasmonic waveguide up to 43% is obtained after normalizing to reference waveguides at 1550   nm . This coupling scheme can be potentially used for fast optical switching and small-footprint optical modulation.