Discriminative sensing of temperature and acoustic impedance by using forward Brillouin scattering in large effective area fiber

Abstract

We experimentally clarified the characteristics of forward Brillouin scattering induced by radial acoustic modes (R 0,m ) in large effective area fiber. The measured resonance frequencies of R 0,m modes were shown to have different sensitivities to acoustic impedance. Then we performed discriminative measurement of temperature and acoustic impedance by selecting a pair of different R 0,m modes that would achieve the minimum measurement error, where we had successfully achieved small measurement uncertainties of 0.4 °C and 0.03 kg·s–1 · mm–2, respectively.