Gap FBG and its application in tunable narrow linewidth fiber laser

Yuanhong Yang, Xiaozhe Zhang, Jin Jin Guo, Wei Jin, Mingwei Yang

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review


A gap fiber Bragg grating (g-FBG) is fabricated by cutting a uniform FBG in the middle to introduce a small air gap between the two sections. Numerical and experimental investigations show that the g-FBG has the characteristics of both a phase shifted FBG and a Fizeau interferometer. The peak transmission wavelength of the g-FBG can be tuned by adjusting the air-gap longitudinally or transversely with respect to the fiber center-axis. With a g-FBG as tunable intra-cavity filter, a tunable fiber ring laser with a narrow line-width is demonstrated. The wavelength tuning range of the laser is 0.12 nm with a output power flatness better than 0.9 dB. The 3 dB spectral line-width is less than 12 pm and output power is 3.68 dBm.
Original languageEnglish
Title of host publication22nd International Conference on Optical Fiber Sensors
Publication statusPublished - 1 Dec 2012
Event22nd International Conference on Optical Fiber Sensors - Beijing, China
Duration: 15 Oct 201219 Oct 2012


Conference22nd International Conference on Optical Fiber Sensors


  • Fiber ring laser
  • Gap fiber Bragg grating
  • Tunable filter

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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