The effect of stress-induced birefringence on polarization-dependent transmission characteristics was thoroughly investigated for a long-period fiber grating (LPFG) that was fabricated by use of a stress relaxation method with a CO2 laser. A series of two-dimensional axial stress profiles for one complete period of a LPFG was measured with an optical tomographic measurement technique. We found that the asymmetry in the stress distribution of the cladding was much larger than in the core of the LPFG. The splitting of polarization-dependent loss peaks in the optical transmission spectrum was calculated based on the measured asymmetric stress profiles and was compared with an experimental result.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics