Characteristics of Linearly Polarized Yb-Doped Fiber Laser in an All-Fiber Configuration

Polarization selection in fiber lasers by use of two birefringent fiber Bragg gratings is investigated. When the principal axes of the two gratings are arranged perpendicularly by incorporating one cross splicing and one of the combinations of slow and fast axis Bragg wavelengths is matched, a resonator can be formed only for a single-polarization state. An 8-W 1064-nm linearly polarized Yb-doped fiber laser with an 87% slope efficiency and less than 20-pm bandwidth has been successfully demonstrated. No additional loss in polarization selection is preferable for high efficiency and high-power durability.