We demonstrate a robust 3-dB directional coupler which has a narrow silicon wire core and a wide gap. Sensitivity to the gap variation is decreased to one tenth that of a conventional directional coupler. Better spectral stability due to the enhanced robustness to waveguide geometrical fluctuations was experimentally verified.
No takes yet. Share an insight, caveat, or question.
Cong et al. (2014) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: