Chin. Phys. B ›› 2014, Vol. 23 ›› Issue (1): 14206-014206.doi: 10.1088/1674-1056/23/1/014206

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Irradiation effect on strain sensitivity coefficient of strain sensing fiber Bragg gratings

金靖, 林松, 宋凝芳   

  1. School of Instrument Science and Optic-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China
  • 收稿日期:2013-04-17 修回日期:2013-06-03 出版日期:2013-11-12 发布日期:2013-11-12
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 61007040).

Irradiation effect on strain sensitivity coefficient of strain sensing fiber Bragg gratings

Jin Jing (金靖), Lin Song (林松), Song Ning-Fang (宋凝芳)   

  1. School of Instrument Science and Optic-electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China
  • Received:2013-04-17 Revised:2013-06-03 Online:2013-11-12 Published:2013-11-12
  • Contact: Lin Song E-mail:linsong@aspe.buaa.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61007040).

PDF (PC)

364

赞

摘要： The effect of irradiation on the strain sensitivity coefficient of strain sensing fiber Bragg gratings (FBGs) has been investigated through experiments. FBGs were fabricated in single mode fibers with 3 mol% Ge-concentration in the core and with a H2-loading treatment. In experiments, the FBGs were subjected to γ-radiation exposures using a Co60 source at a dose-rate of 25 Gy/min up to a total dose of 10.5 kGy. The GeO defect in fiber absorbs photons to form a GeE’ defect; the interaction with H2 is a probable reason for the γ-radiation sensitivity of gratings written in hydrogen loaded fibres. The effect mechanism of radiation on the strain sensitivity coefficient is similar to that of radiation on the temperature sensitivity coefficient. Radiation affects the effective index neff, which results in the change of the thermo-optic coefficient and the strain-optic coefficient. Irradiation can change the strain sensitivity coefficient of FBGs by 1.48%–2.71%, as well as changing the Bragg wavelength shift (BWS) by 22 pm–25 pm under a total dose of 10.5 kGy. Our research demonstrates that the effect of irradiation on the strain sensitivity coefficient of FBG is small and that strain sensing FBGs can work well in the radiation environment.

关键词: fiber Bragg grating, irradiation effect, strain sensitivity coefficient

Abstract: The effect of irradiation on the strain sensitivity coefficient of strain sensing fiber Bragg gratings (FBGs) has been investigated through experiments. FBGs were fabricated in single mode fibers with 3 mol% Ge-concentration in the core and with a H2-loading treatment. In experiments, the FBGs were subjected to γ-radiation exposures using a Co60 source at a dose-rate of 25 Gy/min up to a total dose of 10.5 kGy. The GeO defect in fiber absorbs photons to form a GeE’ defect; the interaction with H2 is a probable reason for the γ-radiation sensitivity of gratings written in hydrogen loaded fibres. The effect mechanism of radiation on the strain sensitivity coefficient is similar to that of radiation on the temperature sensitivity coefficient. Radiation affects the effective index neff, which results in the change of the thermo-optic coefficient and the strain-optic coefficient. Irradiation can change the strain sensitivity coefficient of FBGs by 1.48%–2.71%, as well as changing the Bragg wavelength shift (BWS) by 22 pm–25 pm under a total dose of 10.5 kGy. Our research demonstrates that the effect of irradiation on the strain sensitivity coefficient of FBG is small and that strain sensing FBGs can work well in the radiation environment.

Key words: fiber Bragg grating, irradiation effect, strain sensitivity coefficient

中图分类号:  (Fiber testing and measurement of fiber parameters)

  • 42.81.Cn
42.82.Et (Waveguides, couplers, and arrays) 42.88.+h (Environmental and radiation effects on optical elements, devices, and systems)