Ultrafast Temperature Interrogation Using an In-Line Mach Zehnder Interferometer Based on Optical Time-Stretching

An ultrafast temperature interrogating system based on the optical time-stretch method and a no core fiber-side hole fiber -no core fiber (NC-SH-NC) structure is proposed and experimentally demonstrated. The NC-SH-NC structure is working as a sensing element and comb filter to modulate the optical pulse. Differ from traditional spectral demodulation method. The wavelength shift is converted into time domain pulse drift by employing a dispersive element. The sensitivity of the structure to temperature is 0.581 dBm/℃ (wavelength demodulation), -294 µV/℃ and 50 ns/℃ (time domain demodulation) respectively.