Ultra-compact broadband 3-db metal–dielectric-metal plasmonic power splitter

Abstract

Power splitters are considered essential components in optical interconnects. In this research work, two different designs of 1×2 3-dB small-footprint high-performance plasmonic power splitters with less than 1% loss in each branch are proposed and numerically investigated using the finite-difference-time-domain method. Based on the simulation results, we show that unequal splitting ratio can be achieved by breaking the symmetry of the two plasmonic branches either by changing the width or the position of one of the splitter branches with respect to the other one. Moreover, the proposed splitters’ designs have the advantage of improving the alignment tolerance of the two plasmonic branches with respect to the centre of the dielectric waveguide in addition to broadening the spectrum response of the splitter. Our proposed technique can be extended to 1×N power splitters in addition to being employed in various high density photonic integration and nano-plasmonic circuits such as directional couplers and Mach–Zehnder interferometers.