In-line Mach-Zehnder interferometer based on a dissimilar-doping dual-core fiber for high sensitivity strain and temperature sensing

A dual-core fiber in which one of the cores is doped with Germanium and the other with Phosphorus is used as an in-line Mach-Zehnder (MZ) interferometer to perform high sensitivity strain and temperature sensing. Opposite sensitivities for high and low wavelength peaks were demonstrated when strain was applied. To our knowledge this is the first time that such behavior is demonstrated using this type of in-line MZ interferometer based on a dual-core fiber. A sensitivity of (78±2) pm/με, between 0-950 με and (1380±20) pm/ºC between 45 and 80ºC is demonstrated. It was also demonstrated that it is possible to use this configuration for simultaneous measurement of strain and temperature and a matrix equation to calculate them was givenMinisterio de Economía y CompetitividadEuropean Commissio