Characterization and control of polarization in hollow core photonic bandgap fiber

Abstract

For the demonstration of all hollow core photonic bandgap fiber (HC-PBFG) polarization controller, intrinsic phase and group birefringence of the fiber were measured qualitatively by using various methods for different wavelengths. Not only intrinsic birefringence but also twist was quantitatively measured for different external twists. A local birefringence perturbation from bending was exploited to confirm the previous result of intrinsic birefringence and twist. The magnitude and axis of bending birefringence were shown to be different from a conventional solid-core fiber. Based on the results, the possibility of a demonstration of a bending type polarization controller was discussed.