Measurement of concentration and temperature using a fiber loop ring-down technique with core-offset structure

作者：Wang, Fang; Lu, Heng; Wang, Xu; Liu, Yufang^*

来源：Optics Communications, 2018, 410: 13-16.

DOI：10.1016/j.optcom.2017.09.092

• Fiber-loop ring-down
• Concentration
• Temperature
• Core-offset
• Interference

Fiber-loop ring-down spectroscopy (FLRDS) technique can be used for measurement by indirectly measuring the ring-down time. This is advantageous because it is free from fluctuations of the light source and has a high sensitivity. A novel sensing system for measuring the concentration and temperature based on the FLRDS technique and Mach-Zehnder interferometer (MZI) is proposed in this work. The intra-cavity losses were compensated, which depended on the erbium-doped fiber amplifier. The sensor head was a section of 4 cm single-mode fiber that was spliced into the fiber loop ring cavity in a core-offset way, and its characteristics were tested by experimenting with different solution concentrations and temperatures. The experimental results showed that the detection limit of this system is 0.0014 g/ml, in the range of 0.010-0.400 g/ml. In the temperature sensing experiment, when the temperature varied from 30-200 degrees C, a sensitivity of 1.83 mu s/degrees C was achieved. This research demonstrated that the MZI-based FLRDS sensing system has a clear response to the solution and temperature; therefore, it provides a reference for the measurement of stress, pressure, curvature, and other physical quantities.

• 出版日期2018-3-1
• 单位河南师范大学