Configurable lossless broadband beam splitters for semi-guided waves in integrated silicon photonics

We show that narrow trenches in a high-contrast silicon-photonics slab can act as lossless power dividers for semi-guided waves. Reflectance and transmittance can be easily configured by selecting the trench width. At sufficiently high angles of incidence, the devices are lossless, apart from material attenuation and scattering due to surface roughness. We numerically simulate a series of devices within the full 0-to-1-range of splitting ratios, for semi-guided plane wave incidence as well as for excitation by focused Gaussian wave bundles. Straightforward cascading of the trenches leads to concepts for 1xM-power dividers and a polarization beam splitter. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

By processing narrow trenches on high-contrast silicon-photonics slabs, lossless power division for semi-guided waves can be achieved, with reflectance and transmittance configurable by selecting trench width. Devices at high angles of incidence are lossless, except for material attenuation and scattering, cascading trenches for 1xM-power dividers and polarization beam splitters is possible.