Optical fiber strain and temperature sensor based on an in-line Mach-Zehnder interferometer using thin-core fiber

摘要

We propose and demonstrate a fiber in-line Mach-Zehnder interferometer using thin-core fibers. This in-line interferometer is composed of a short section of thin-core fiber inserted between two single mode fibers (SMF), and demonstrated as a strain and temperature sensor in this study. A strain sensitivity of -1.83 pm/(mu)(epsilon) with a measurement range of 0-2000 (mu)(epsilon), and the temperature sensitivity of -72.89 pm/deg C with a temperature variation of 50 deg C are achieved. We also discussed that the influence of strain and temperature change on the relative power ratios among the excited cladding modes in thin-core fibers.