title: Pump polarization insensitive and efficient laser-diode pumped Yb:KYW ultrafast oscillator.
abstract: We theoretically and experimentally report and evaluate a novel split laser-diode (LD) double-end pumped Yb:KYW ultrafast oscillator aimed at improving the performance of an ultrafast laser. Compared to a conventional unpolarized single-LD end-pumped ultrafast laser system, we improve the laser performance such as absorption efficiency, slope efficiency, cw mode-locking threshold, and output power by this new structure LD-pumped Yb:KYW ultrafast laser. Experiments were carried out with a 1 W output fiber-coupled LD. Experimental results show that the absorption increases from 38.7% to 48.4%, laser slope efficiency increases from 18.3% to 24.2%, cw mode-locking threshold decreases 12.7% from 630 to 550 mW in cw mode-locking threshold, and maximum output-power increases 28.5% from 158.4 to 221.5 mW when we switch the pump scheme from an unpolarized single-end pumping structure to a split LD double-end pumping structure.
authors.forename: Sha
authors.initials: S
authors.lastname: Wang
authors.forename: Yan-Biao
authors.initials: YB
authors.lastname: Wang
authors.forename: Guo-Ying
authors.initials: GY
authors.lastname: Feng
authors.forename: Shou-Huan
authors.initials: SH
authors.lastname: Zhou