Brillouin Spectrum in LEAF and Simultaneous Temperature and Strain Measurement

The triangle refractive index profile of LEAF fiber (a non-zero dispersion shifted fiber) makes it much more sensitive to temperature and strain. Owing to its high stimulated Brillouin scattering (SBS) threshold for long distance distributed sensors, we studied the Brillouin spectrum characteristics of LEAF under different strain and temperature conditions. The results are compared with those of SMF-28. Based on the linear relationship between the four peaks' linewidth/peak frequency and strain/temperature, we achieved a strain error of 37 με and a temperature error of 1.8
^°
C with a spatial resolution of 4 m for simultaneous temperature and strain measurement.