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Article Abstract
A novel, to the best of our knowledge, mid-infrared chalcogenide (ChG) on magnesium fluoride () waveguide gas sensor was fabricated by using the lift-off method. was used as a lower cladding layer to increase the external confinement factor for enhancing light-gas interaction. Wavelength modulation spectroscopy (WMS) was used in carbon dioxide () detection at the wavelength of 4319 nm (2315.2). The limit of detection for the 1-cm-long sensing waveguide based on WMS is ∼0.3, which is >8 times lower than the same sensor using direct absorption spectroscopy (DAS). The combination of WMS with the waveguide gas sensor provides a new measurement scheme for the performance improvement of on-chip gas detection.
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| http://dx.doi.org/10.1364/OL.440361 | DOI Listing |
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