Open AccessFocused apodized forked grating coupler
Author(s) -
Christopher T. Nadovich,
William D. Jemison,
Derek J. Kosciolek,
David T. Crouse
Publication year - 2017
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.026861
Subject(s) - apodization , optics , grating , photonics , multiplexing , materials science , fiber bragg grating , diffraction grating , holography , crosstalk , diffraction efficiency , optoelectronics , optical fiber , physics , computer science , telecommunications
The forked grating coupler (FGC) is an optical vortex interface for silicon photonics. Using the structure of a Bragg grating coupler with a calculated forked hologram, the FGC couples optical vortex modes into confined waveguide modes of a photonic integrated circuit. Design methodologies are given, as well as measured performance data from fabricated devices. Data are analyzed with a variety of metrics. The effectiveness of design features are evaluated. Advanced FGC designs are demonstrated with focused forked gratings, allowing feed length to be reduced, and with apodization improving vortex mode fidelity. Some configurations achieve over 25 dB multiplexing crosstalk isolation.