Open AccessSilicon microring refractometric sensor for atmospheric CO_2 gas monitoring
Author(s) -
Guangcan Mi,
Cameron Horvath,
Mirwais Aktary,
Vien Van
Publication year - 2016
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.24.001773
Subject(s) - materials science , refractive index , resonator , absorption (acoustics) , silicon , optoelectronics , photonics , optics , polymer , polydimethylsiloxane , layer (electronics) , nanotechnology , physics , composite material
We report a silicon photonic refractometric CO(2) gas sensor operating at room temperature and capable of detecting CO(2) gas at atmospheric concentrations. The sensor uses a novel functional material layer based on a guanidine polymer derivative, which is shown to exhibit reversible refractive index change upon absorption and release of CO(2) gas molecules, and does not require the presence of humidity to operate. By functionalizing a silicon microring resonator with a thin layer of the polymer, we could detect CO(2) gas concentrations in the 0-500ppm range with a sensitivity of 6 × 10(-9) RIU/ppm and a detection limit of 20ppm. The microring transducer provides a potential integrated solution in the development of low-cost and compact CO(2) sensors that can be deployed as part of a sensor network for accurate environmental monitoring of greenhouse gases.