Brillouin signal amplification in pumped erbium-doped optical fiber

Abstract

Amplification of Brillouin scattering signal extends the measurement range and improves the signal-to-noise ratio of fiber-optic distributed Brillouin sensors. Here, we investigate the amplification effect of a 980-nm pump laser on Brillouin gain spectrum in an erbium-doped optical fiber. The Brillouin-scattered Stokes power increased exponentially with increasing pump power, exhibiting approximately 87% enhancement at 252 mW compared with the Stokes power obtained without the pump. This suggests that a more significant increase in the Stokes power is feasible with a higher-power 980-nm pump laser.

Discriminative strain and temperature measurement using Brillouin scattering and fluorescence in erbium-doped optical fiber

“…The experimental setup is depicted in Fig. 1 for exciting Brillouin scattering in an EDF, and the other at 980 nm for enhancing the Brillouin scattering power [24] as well as for exciting the fluorescence in the EDF. During the FIR measurement, the LD at 1550 nm was not operated.…”

“…During the FIR measurement, the LD at 1550 nm was not operated. The Brillouin Stokes light was heterodyned with the reference light, converted into an electrical signal with a photo diode, and then observed as BGS with an electrical spectrum analyzer (see [24] for details). The fluorescence spectrum of the EDF was observed with an optical spectrum analyzer (OSA).…”

Brillouin scattering in multi-core optical fibers for sensing applications

“…Such special fibers include tellurite glass fibers 25 26 , chalcogenide glass fibers 27 28 , bismuth-oxide glass fibers 26 29 , photonic crystal fibers (PCFs) 30 , rare-earth-doped glass fibers (REDFs) 31 32 , polymethyl methacrylate (PMMA)-based polymer optical fibers (POFs) 33 , and perfluorinated graded-index (PFGI) POFs 34 35 . Each special fiber has its own unique advantage; for instance, the Brillouin-scattered Stokes powers in tellurite and chalcogenide fibers are much higher than those in silica SMFs, owing to their large Brillouin gain coefficients 25 26 27 28 ; the Stokes powers in REDFs can be adjusted by controlling the pumping light power (at 980 nm in erbium-doped fibers (EDFs)) 32 36 ; and Brillouin scattering in POFs is potentially applicable to high-sensitivity temperature measurement 35 as well as large-strain measurement 37 . Similarly, if Brillouin-scattered signals from multiple cores of an MCF can be simultaneously exploited, a discriminative measurement of strain and temperature 38 39 40 41 will be feasible by using a single fiber, as discussed below.…”