Distributed temperature–strain sensor based on inter-mode Kerr four-wave mixing of PMF: proposal and proof-of-concept

Abstract

A novel concept of distributed temperature-strain sensors is proposed using inter-mode Kerr four-wave mixing of polarization-maintaining fiber (PMF), in which the dominated physical mechanism is basically different from reported Brillouin dynamic grating (BDG). The independent measurement for temperature and strain sensitivities (-0.431 MHz/℃ and 0.067 MHz/10 µɛ) was completed by detecting the change in birefringence under pump-Stokes frequency separation at 370 MHz. As a preliminary proof-of-concept, sensing with spatial resolution of ~ 5 m was demonstrated along ~210 m PMF. Compared with BDG, the proposed sensor features potential of multiple parameters measurement including temperature-strain and liquid acoustic impedance.