Sensitive Mach–Zehnder interferometric sensor based on a grapefruit microstructured fiber by lateral offset splicing

A novel inline Mach-Zehnder interferometric (MZI) sensor based on a homemade grapefruit microstructured fiber (GMF) was proposed and experimentally demonstrated. The sensing unit consists of a short segment of a GMF sandwiched between two single mode fibers using lateral offset splicing. The fabrication of the GMF and the GMF-based MZI sensor was introduced. Mode analysis of the GMF and theoretical simulation of the proposed MZI sensor were investigated and matched well with experimental results. The sensing performance of the MZI sensor for temperature and strain was tested. The strain and temperature sensitivity are 1.97pm/µε and 37pm/°C, respectively. The compact size, low cost and high sensitivity makes the MZI sensor a good candidate for sensing application.