Axial Micro-Strain Sensor Based on Resonance Demodulation Technology Via Dual-Mode CMECF
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This paper firstly and experimentally demonstrates an in-fiber axial micro-strain sensing head, combined with a Mach-Zehnder interferometer (MZI) based on the concentric multilayer elliptical-core fiber (CMECF). This MZI with a high extinction ratio (about 15 dB) is successfully achieved with a CMECF-single mode fiber-CMECF (CSC) structure. The MZI sensor theory and the resonance demodulation technology are systematically described in this paper. In this CSC structure, two sections of the CMECF have a role as the mode generator and coupler, respectively. LP01 and LP11even, which have similar excitation coefficients, are two dominated propagating mode groups supported in the CMECF. On account of the distinct dual-mode property, a good stability of this sensor is realized. The detected resonance in the MZI shifts as the axial micro-strain variated due to the strong interaction between higher order modes. High sensitivity of ∼1.78 pm/με is experimentally achieved within the range of 0 με–1250 με, meanwhile, the intensity fluctuation is below 0.38 dB.
KeywordsFew-mode fiber fiber sensor MZI axial micro-strain
This work was supported by the Major State Basic Research Development Program of China (Granted No. 2010CB328206), the “Double Tops” Construction Funds of Minzu University of China (Granted No. 018004032101), the Young Teachers’ Research Project of Minzu University of China, and in part by the Fundamental Research Funds for the Central Universities, China.
- T. Zhao, Y. Gong, Y. J. Rao, Y. Wu, Z. L. Ran, and H. J. Wu, “Fiber-optic Fabry-Perot strain sensor based on graded-index multimode fiber,” Chinese Optics Letters, 2011, 9(5): 11–14.Google Scholar
- C. Xia, R. A. Correa, N. Bai, E. A. Lopez, D. M. Arrioja, A. Schulzgen, et al., “Low-crosstalk few-mode multi-core fiber for high-mode-density space-division multiplexing,” in Proceeding of 2012 38th European Conference and Exhibition on Optical Communications, Amsterdam, Netherlands, 2012, pp. 1–3.Google Scholar
- T. Geisler, M. E. V. Pedersen, and S. Herstrøm, “Measurement of spatial and polarization birefringence in two-mode elliptical core fibers,” in Proceeding of 2013 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference, Anaheim, CA,USA, 2013, pp. 1–3.Google Scholar
- C. C. Wong, M. C. Su, and N. S. Lin, “A compact all fiber refractive index sensor based on modal interference,” IEEE Sensors, 2012, 3(11): 1–4.Google Scholar
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