Photonic Crystal Fiber Strain Sensor Based on Modified Mach–Zehnder Interferometer

In this paper, a novel strain sensor is proposed and demonstrated by employing a modified photonic crystal fiber (PCF)-based Mach–Zehnder interferometer, in which a collapsed region is introduced at the middle point of the PCF to improve the extinction ratio. Experimental results show that this proposed structure has a high sensitivity of 11.22
$\hbox{dB/m}\varepsilon$
over a range of 1.28
$\hbox{m}\varepsilon$
and high-temperature stability.