<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a m...<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a multi-layer few-mode fiber (ML-FMF), and could acquire the change of the axial strain along fibers, which depends on the transmission dips. On account of the distinct dual-mode property, a good stability of this sensor is realized. The two transmission dips could have the different sensing behaviors. Both the propagation characteristics and operation principle of such a sensor are demonstrated in detail. High sensitivity of the FM-FBG, ~4 pm/με and ~4.5 pm/με within the range of 0 με - 1456 με, is experimentally achieved. FM-FBGs could be easily scattered along one fiber. So this sensor may have a great potential of being used in sensor networks. </div>展开更多
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 w...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 15dB)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 LPlleven,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^1.78pm/με is experimentally achieved within the range of 0με-1250με,meanwhile,the intensity fluctuation is below 0.38dB.展开更多
文摘<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a multi-layer few-mode fiber (ML-FMF), and could acquire the change of the axial strain along fibers, which depends on the transmission dips. On account of the distinct dual-mode property, a good stability of this sensor is realized. The two transmission dips could have the different sensing behaviors. Both the propagation characteristics and operation principle of such a sensor are demonstrated in detail. High sensitivity of the FM-FBG, ~4 pm/με and ~4.5 pm/με within the range of 0 με - 1456 με, is experimentally achieved. FM-FBGs could be easily scattered along one fiber. So this sensor may have a great potential of being used in sensor networks. </div>
文摘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 15dB)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 LPlleven,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^1.78pm/με is experimentally achieved within the range of 0με-1250με,meanwhile,the intensity fluctuation is below 0.38dB.