Pedestal waveguides based on GeO2-Bi2O3, GeO2-PbO, Ta2O5 and SiOxNy cores as platforms for optical amplifiers and nonlinear optics applications: Review of recent advances

In this review we present recent advances regarding pedestal waveguides using different cores based on GeO2-Bi2O3, GeO2-PbO, Ta2O5 and SiOxNy materials for optical amplifiers and nonlinear optics applications. The pedestal platform, based on Si technology, is interesting for materials that are hardly etched by conventional techniques as is the case of heavy metal oxide cores. The present results review recent technological advances to fabricate pedestal waveguides with and without Cr mask. The fabrication mechanism that does not use Cr mask and avoids micromasking effect is shown. The advantages of this process are discussed as well as its appropriateness to produce pedestal waveguides for optical amplification at 1.53 μm and nonlinear optics applications. Comparison with pedestal waveguides prepared with Cr mask is also included to highlight the advantages that the new technique performed in the absence of Cr mask may provide, regarding propagation losses at the infrared region. Results of pedestal waveguides performance improvement, due to the scattering of large silicon nanostructures is also reviewed opening new possibilities for more efficient pedestal waveguides for optical amplification. •Recent advances of pedestal waveguides: optical amplifiers and nonlinear optics.•Pedestal platform: alternative for materials that are hardly etched.•Pedestal waveguides of Ta2O5 and SiOxNy cores: suitable for nonlinear optics.•Optical amplifiers based on GeO2-PbO and GeO2-Bi2O3 cores: operation at 1.53 μm.•Pedestal waveguides fabrication processes: with and without Cr mask.