Microstructured fiber Mach-Zehnder interferometers for simultaneous measurement of axial strain and temperature

Three different types of microstructured asymmetrical fiber Mach-Zehnder interferometers (aFMZIs) consisting of a fiber taper, a lateral-shifted junction, or a femtosecond laser irradiated spot are demonstrated to realize simultaneous measurement of axial strain and temperature. These aFMZIs of different device architectures exhibit different environmental sensitivities. For the taper/junction type aFMZI, the experimental results indicate temperature sensitivities of 60.6 and 64.0 pm/degrees C (redshifts) and strain sensitivities of -1.48 and -2.72 pm/mu epsilon (blueshifts) at higher and lower interference orders m(1) (49) and m(2) (48), respectively. The other taper/spot and junction/spot type aFMZIs show similar performance and demonstrate the effectiveness of the approach.