Polarization-independent photonic Bragg grating filter with cladding asymmetry

Journal Article · Wed Feb 22 00:00:00 EST 2023 · Optics Letters

DOI:https://doi.org/10.1364/OL.479600· OSTI ID:1958078

Pimbi, Daniel ; Hasan, Mehedi; Borhan Mia, Md ; Jaidye, Nafiz; Kim, Sangsik

A photonic Bragg grating is a fundamental building block that reflects the direction of wave propagation through spatial phase modulation and can be implemented using sidewall corrugation. However, due to the asymmetric aspect ratio of a waveguide cross section, typical Bragg gratings exhibit a strong polarization sensitivity. Here, we show that photonic Bragg gratings with cladding asymmetry can enable polarization-independent notch filters by rotating input polarizations. Such Bragg gratings strongly couple transverse electric (TE) and transverse magnetic (TM) modes propagating in opposite directions, filtering the input signal and reflecting the rotated mode. We analyzed this polarization-rotating Bragg grating using the coupled-mode theory and experimentally demonstrated it on a silicon-on-insulator platform. Our device concept is simple to implement and compatible with other platforms, readily available as polarization transparent Bragg components.

• Sponsoring Organization: USDOE
• Grant/Contract Number: NA-0003525
• OSTI ID: 1958078
• Journal Information: Optics Letters, Journal Name: Optics Letters Vol. 48 Journal Issue: 5; ISSN 0146-9592
• Publisher: Optical Society of America
• Country of Publication: United States
• Language: English