Π-Phase Shifted Fiber Bragg Grating-Website Name

Π-Phase Shifted Fiber Bragg Grating

Phase-shifted fiber Bragg gratings refer to the introduction of a refractive index modulation mutation at a certain position in the middle of the fiber Bragg grating (FBG), generating a fiber Bragg grating with a fixed phase mutation at this position. These two gratings are similar to wavelength-selective Fabry-Perot resonators, allowing light of the resonant wavelength to be injected into the stopband of the FBG. Thus, a linearly extremely narrow refraction window is opened in the stopband. In the field of lasers, phase-shifted fiber gratings are mainly used to fabricate low-noise single-frequency narrow-linewidth fiber lasers, ensuring resonance within the laser cavity with their ultra-narrow narrowband transmission peaks and large free spectral range.

Phase-shifted fiber Bragg gratings refer to the introduction of a refractive index modulation mutation at a certain position in the middle of the fiber Bragg grating (FBG), generating a fiber Bragg grating with a fixed phase mutation at this position. These two gratings are similar to wavelength-selective Fabry-Perot resonators, allowing light of the resonant wavelength to be injected into the stopband of the FBG. Thus, a linearly extremely narrow refraction window is opened in the stopband.
In the field of lasers, phase-shifted fiber gratings are mainly used to fabricate low-noise single-frequency narrow-linewidth fiber lasers. With their ultra-narrow narrowband transmission peaks and large free spectral range, they ensure that the mode within the resonant laser cavity is only a single longitudinal mode, thereby obtaining stable single-mode narrow-linewidth lasers. Or it can be used for single-frequency semiconductor external cavity laser feedback to achieve narrow-linewidth laser output. In other fields, phase-shifted fiber gratings are mainly used as demultiplexers in dense wavelength division multiplexing (DWDM) systems. The magnitude, position and number of phase shift points have a significant impact on the performance of this demultiplexer.
The characteristics of phase-shifted fiber gratings: extremely narrow linewidth, multi-channel, flexible combination, low loss, and low polarization crosstalk optimization.