Compressive dual-comb spectroscopy in the long-wave infrared region

We present a compressive sensing framework for long-wave infrared dual-comb spectroscopy over 7.5-11.5 μm, enabling accurate spectral reconstruction from undersampled interferograms. For single-species N₂O detection, spectral fidelity is preserved up to a compression factor of 20, with <i>L</i>₂ norm residuals below 1.3 × 10^-4. The retrieved N₂O concentrations maintain over 90% accuracy for compression factors up to 30. In the mixtures of CH₄, N₂O, and C₂H₄, all species are retrieved within 10% relative deviation up to a compression factor of 50. These results demonstrate that the proposed framework enables scalable, computationally efficient deployment of practical DCS systems for real-time trace gas sensing in resource-limited measurement scenarios.