Grating coupler devices provide efficient, foundry-compatible vertical fiber-to-chip coupling solutions in integrated photonic platforms. However, standard grating coupler designs are highly polarization sensitive, which hinders their adoption. We present a new, to the best of our knowledge, type of 1D polarization-insensitive grating coupler (PIGC) that is based on a zero-birefringence subwavelength “corelet” waveguide. We demonstrate a PIGC for coupling in the telecommunications O-band in a 45-nm-node monolithic silicon-on-insulator (SOI) CMOS electronic-photonic platform, with measured insertion losses of 6.7 and 6.1 dB to transverse electric and transverse magnetic polarizations, respectively, and a ±1-dB polarization dependent loss bandwidth of 73 nm.
Bragg-grating based cavities and coupler designs present opportunities for flexible allocation of bandwidth and spectrum in silicon photonic devices. Integrated silicon photonic devices are moving toward mainstream, mass adoption, leading to the need for compact Bragg grating based designs. In this work we present a design and experimental validation of a cascaded contra-directional Bragg-grating coupler with a measured main lobe to side-lobe contrast of 12.93 dB. This level of performance is achieved in a more compact size as compared to conventional apodized gratings, and a similar design philosophy can be used to improve side-lobe reduction in grating-based mirror design for on-chip lasers and other cavity-based designs as well.
more » « less- NSF-PAR ID:
- 10531226
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 30
- Issue:
- 6
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 9983
- Size(s):
- Article No. 9983
- Sponsoring Org:
- National Science Foundation
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