Research on performance of fiber twist sensors based on reflective microfiber couplers

Fiber twist sensors based on reflective microfiber couplers (RMCs) with two different fiber types are proposed and investigated. The single-mode fiber RMC (S-RMC) is fabricated by fusing and tapering two single-mode fibers and then connecting two fibers to form a Sagnac loop. The polarization-maintaining fiber RMC (P-RMC) is fabricated by the same method but consist of a segment of polarization-maintaining fiber. The S-RMC and the P-RMC achieve twist sensitivity of 2621.08 (a.u.)/(rad/m) and 2355.59 (a.u.)/(rad/m), respectively. For S-RMC, the wavelength and intensity fluctuations are <0.1 nm (0.05 nm/degrees C) and 0.2 dB (0.01 dB/degrees C) at temperatures ranging from 25 degrees C to 45 degrees C, respectively. The S-RMC has the characteristics of high twist sensitivity and linearity, thermal stability, low loss as well as easy fabrication.

Automated summary

The research proposes fiber twist sensors based on reflective microfiber couplers with different types of fibers. It found that the single-mode fiber RMC and the polarization-maintaining fiber RMC have high twist sensitivity, linearity, thermal stability, and low loss.