High-coherence mid-infrared dual-comb spectroscopy spanning 2.6 to 5.2 μm

By G. Ycas, F. Giorgetta, Esther Baumann, Ian Coddington, D. Herman, Scott A. Diddams, Nathan R. Newbury. 2017

305 citations recorded by the source corpus.

Mid-infrared dual-comb spectroscopy has the potential to supplant conventional Fourier-transform spectroscopy in applications requiring high resolution, accuracy, signal-to-noise ratio and speed. Until now, mid-infrared dual-comb spectroscopy has been limited to narrow optical bandwidths or low signal-to-noise ratios. Using digital signal processing and broadband frequency conversion in waveguides, we demonstrate a mid-infrared dual-comb spectrometer covering 2.6 to 5.2 µm with comb-tooth resolution, sub-MHz frequency precision and accuracy, and a spectral signal-to-noise ratio as high as 6,500. As a demonstration, we measure the highly structured, broadband cross-section of propane from 2,840 to 3,040 cm−1, the complex phase/amplitude spectra of carbonyl sulfide from 2,000 to 2,100 cm−1, and of a methane, acetylene and ethane mixture from 2,860 to 3,400 cm−1. The combination of broad bandwidth, comb-mode resolution and high brightness will enable accurate mid-infrared spectroscopy in precision laboratory experiments and non-laboratory applications including open-path atmospheric gas sensing, process monitoring and combustion.By employing difference-frequency generation, a mid-infrared dual-comb spectrometer covering the 2.6 to 5.2 µm range is demonstrated with comb-tooth resolution, sub-MHz frequency precision and accuracy, and a spectral signal-to-noise ratio as high as 6,500.

Subfields: Atomic and Molecular Physics, and Optics, Electrical and Electronic Engineering, Spectroscopy

View Paper: https://www.semanticscholar.org/paper/b9e0a1333eee5dc774faabeb03d41fd9ace35860