PMD stability in small-core photonic crystal fiber during mechanical and thermal tests

The influence of mechanical factors: twisting, bending and temperature on polarization parameters, in particular the polarization mode dispersion (PMD) of photonic crystal fiber (PCF) has been experimentally investigated. The PCF used was a highly nonlinear, highly birefringent fiber with small GeO₂ doped core. It has shown a greatly superior stability of PMD in comparison to conventional telecom single-mode fibers, including PANDA and Bow-Tie birefringent fibers. Such properties are useful for several applications where introduction of controlled optical birefringence into fiber link is required, e.g. calibration of PMD test equipment.