Correcting photodetector nonlinearity in dual-comb interferometry
arXiv:2107.02138 · doi:10.1364/OE.435701
Abstract
Photodetector nonlinearity, the main limiting factor in terms of optical power in the detection chain, is corrected to improve the signal-to-noise ratio of a short-time measurement in dual-comb spectroscopy. An iterative correction algorithm minimizing out-of-band spectral artifacts based on nonlinearity correction methods used in classical Fourier-transform spectrometers is presented. The exactitude of the nonlinearity correction is validated using a low power linear measurement. Spectroscopic lines of HCN are provided and the error caused by the saturation of the detector is corrected yielding residuals limited by the measurement noise.
10 pages, 7 figures