In this paper, we demonstrate silicon-on-insulator (SOI) channel waveguides with propagation loss and r = 10 μm bends with bending loss as low as 2 dB/cm and 0.02 dB/90◦ in the broad wavelength range of 3.68–3.88 μm. We also indicate the limitation of SOI waveguide loss in mid-infrared wavelength by analyzing loss mechanisms. Based on this high-performance mid-infrared waveguide, we systematically analyze the coupling efficiency of various directional couplers, which are critical and commonly used building blocks
for on-chip light routing and power splitting. By varying coupling length and sweeping wavelength, the performance of directional coupler with various gap separations is meticulously investigated in 3.68–3.88 μm. A experimental database for directional coupler with any power splitting ratio is provided. Our results offer a promising broadband platform for dense wavelength division multiplexing (DWDM) and applications that require precise control of coupling such as racetrack resonator in the mid-infrared region.
License type:
PublisherCopyrights
Funding Info:
Description:
(c) 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.