Broadband multimode 3 dB optical power splitter using tapered couplers

Abstract

A design of a 1 × 2 multimode 3 dB optical power splitter using tapered couplers is proposed and investigated in this paper. As an example, a 1 × 2 splitter processing five-lowest order transverse-electric-polarized modes is designed and optimized by utilizing finite difference time domain method and particle swarm optimization algorithm. To verify the feasibility of this novel design, the optimized device is fabricated on a silicon-on-insulator platform. The coupling lengths of tapered couplers are respectively 6.5 µm, 6.0 µm, 3.5 µm, 5.0 µm, 5.0 µm, 7.5 µm, 6.0 µm, 5.0 µm, and 8.0 µm. Measurement results reveal that, for the fabricated splitter, the power uniformity varies from 0.041 to 0.88 dB, the crosstalk ranges from -23.96 to -14.12 dB, and the insertion loss changes from 0.089 to 1.50 dB within a bandwidth from 1520 to 1600 nm.