Dynamic strain measurement by a single-slope-assisted chaotic Brillouin optical correlation-domain analysis

We propose a novel, to the best of our knowledge, method to enhance the measurement range of dynamic strain using a single-slope-assisted chaotic Brillouin optical correlation-domain analysis. The broadband chaos provides a Gaussian-shape pump-probe beat spectrum so that not only the centimeter-level spatial resolution is achieved but also the linewidth of the chaotic Brillouin gain spectrum is naturally broadened. Thus, the enlarged linear region could be employed to dynamically measure a large-range stretched strain. This experiment is the first to accurately identify the maximal strain of 1200 $\unicode{x00B5}\unicode{x03B5}$µε with a high spatial resolution of 3.45 cm using the single-slope-assisted technology. The dynamic frequency is 4.67 Hz in the highest but limited by the practical devices.