1. Anti-reflection subwavelength gratings for InP-based waveguide facets
- Author
-
Lukas Puts, Sander Reniers, Jens H. Schmid, Pavel Cheben, Daniele Melati, Xaveer Leijtens, and Photonic Integration
- Subjects
Core (optical fiber) ,Wavelength ,Materials science ,Reflection (mathematics) ,Optics ,law ,business.industry ,Astronomical interferometer ,Physics::Optics ,business ,Waveguide ,Atomic and Molecular Physics, and Optics ,law.invention - Abstract
We demonstrate the anti-reflection properties of lithographically defined subwavelength gratings applied to the facets of integrated waveguides realized in the InP membrane-on-silicon platform. The subwavelength gratings are based on the gradient index effect to create a smooth index transition between the core material and air, making it possible to obtain reflections below − 30 d B at a wavelength of 1550 nm for both TE and TM polarized modes, as shown by 3D finite-difference time-domain simulations. Characterizations performed using Mach–Zehnder interferometers as test structures show relative reflections as low as − 25 d B , confirming the effectiveness of the technique.
- Published
- 2021