Volume detection based on porous silicon waveguide for CO mid-infrared spectroscopy.

A mid-infrared (mid-IR) porous silicon (PSi) waveguide gas sensor was fabricated. PSi guiding and confinement layers were prepared by electrochemical anodization. Ridge waveguides were patterned using standard i-line photolithography and reactive ion etching.

Carbon dioxide mid-infrared sensing based on Dy-doped chalcogenide waveguide photoluminescence.

Climate-active gases, notably carbon dioxide (CO), methane (CH), and nitrous oxide (NO), display fundamental absorption bands in the mid-infrared (mid-IR). The detection and monitoring of those gases could be enabled by the development of mid-IR optical sources. Broadband mid-IR on-chip light emission from rare-earth-doped chalcogenide photonic integrated circuits could provide a compact, efficient, and cost-effective gas sensing solution.

Theoretical Demonstration of the Interest of Using Porous Germanium to Fabricate Multilayer Vertical Optical Structures for the Detection of SF Gas in the Mid-Infrared.

Porous germanium is a promising material for sensing applications in the mid-infrared wavelength range due to its biocompatibility, large internal surface area, open pores network and widely tunable refractive index, as well as its large spectral transparency window ranging from 2 to 15 μm. Multilayers, such as Bragg reflectors and microcavities, based on porous germanium material, are designed and their optical spectra are simulated to enable SF gas-sensing applications at a wavelength of 10.55 µm, which corresponds to its major absorption line.