
Low-loss demonstration and refined characterization of silicon arrayed waveguide gratings in the near-infrared
Author(s) -
Eric J. Stanton,
Nicolas Volet,
John E. Bowers
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.030651
Subject(s) - arrayed waveguide grating , materials science , optics , transmittance , crosstalk , wavelength division multiplexing , channel spacing , waveguide , optoelectronics , resonator , wavelength , silicon , physics
A resonator is characterized with two cascaded arrayed waveguide gratings (AWGs) in a ring formation. From this structure, the on-chip transmittance of a single AWG is extracted, independent of coupling efficiency. It provides improved measurement accuracy, which is essential for developing AWGs with extremely low loss. Previous methods normalize the off-chip AWG transmittance to that of a reference waveguide with identical coupling, leading to an uncertainty of ∼14 % on the extracted on-chip AWG transmittance. It is shown here that the proposed "AWG-ring" method reduces this value to ∼3 %. A low-loss silicon AWG and an AWG-ring are fabricated. Channel losses with <2 dB are found, with a crosstalk per channel approaching -30 dB. Such an efficient wavelength multiplexing device is beneficial for the integration of spectroscopic sensors, multi-spectral lasers, and further progress in optical communication systems.