High sensitivity strain sensor based on a novel offset-core single micro-tapered fiber-optic Mach-Zehnder interferometer

A novel offset-core single micro-tapered fiber-optic Mach-Zehnder interferometer (MZI) with high strain sensi-tivity is proposed and experimentally demonstrated. This novel structure is fabricated only by using ordinary single mode fiber (SMF) and a fiber fusion splicer, of which the offset-core distance is about 12 mu m and micro -tapered fiber length is about 490 mu m. A high strain sensitivity of-34.61 pm/mu epsilon is obtained, which is 10 times higher than that (3 pm/mu epsilon) of common inline optic-fiber MZI and 6 times higher than that (6 pm/mu epsilon) of common inline optic-fiber Fabry-Perot interferometer (FPI). In addition, the length (-490 mu m) of this novel MZI is much smaller than that of an ordinary inline optic-fiber MZI (-2 cm) with advantages of high sensitivity, low-cost, and easy fabrication. The novel optic-fiber MZI proposed in this paper enriches the manufacturing methods for fiber-optic MZIs, which has a good application prospect for strain sensing.

Automated summary

A novel fiber-optic MZI with high strain sensitivity is proposed in this paper, which is fabricated using ordinary SMF and a fiber fusion splicer, showing potential for strain sensing with its high sensitivity and low-cost advantage.