Low-loss adiabatically-tapered high-contrast gratings for slow-wave modulators on SOI

Corrado Sciancalepore; Karim Hassan; Thomas Ferrotti; Julie Harduin; Hélène Duprez; Sylvie Menezo; Badhise Ben Bakir

doi:10.1117/12.2075334

Translator Disclaimer

27 February 2015 Low-loss adiabatically-tapered high-contrast gratings for slow-wave modulators on SOI

Corrado Sciancalepore, Karim Hassan, Thomas Ferrotti, Julie Harduin, Hélène Duprez, Sylvie Menezo, Badhise Ben Bakir

Author Affiliations +

Proceedings Volume 9372, High Contrast Metastructures IV; 93720G (2015) https://doi.org/10.1117/12.2075334
Event: SPIE OPTO, 2015, San Francisco, California, United States

Abstract

In this communication, we report about the design, fabrication, and testing of Silicon-based photonic integrated circuits (Si-PICs) including low-loss flat-band slow-light high-contrast-gratings (HCGs) waveguides at 1.31 μm. The light slowdown is achieved in 300-nm-thick silicon-on-insulator (SOI) rib waveguides by patterning adiabatically-tapered highcontrast gratings, capable of providing slow-light propagation with extremely low optical losses, back-scattering, and Fabry-Pérot noise. In detail, the one-dimensional (1-D) grating architecture is capable to provide band-edge group indices n_g~ 25, characterized by overall propagation losses equivalent to those of the index-like propagation regime (~ 1-2 dB/cm). Such photonic band-edge slow-light regime at low propagation losses is made possible by the adiabatic apodization of such 1-D HCGs, thus resulting in a win-win approach where light slow-down regime is reached without additional optical losses penalty. As well as that, a tailored apodization optimized via genetic algorithms allows the flattening of slow-light regime over the wavelength window of interest, therefore suiting well needs for group index stability for modulation purposes and non-linear effects generation. In conclusion, such architectures provide key features suitable for power-efficient high-speed modulators in silicon as well as an extremely low-loss building block for non-linear optics (NLO) which is now available in the Si photonics toolbox.

Citation Download Citation

Corrado Sciancalepore, Karim Hassan, Thomas Ferrotti, Julie Harduin, Hélène Duprez, Sylvie Menezo, and Badhise Ben Bakir "Low-loss adiabatically-tapered high-contrast gratings for slow-wave modulators on SOI", Proc. SPIE 9372, High Contrast Metastructures IV, 93720G (27 February 2015); https://doi.org/10.1117/12.2075334

ACCESS THE FULL ARTICLE