Two-stage, co-pumped Yb:silica fiber amplifers

Summary form only given. High peak power laser systems (such as those for fusion or high field physics) require low level input pulses for amplification. Because many of these systems use Nd:phosphate glass, sources and signal amplifiers are needed around 1053 nm. We have developed such devices in single-mode fiber using Yb:silica as the gain medium. This material provides gain flatness in this region for broadband amplification, high saturation fluence for high-energy output, and it can be pumped with commercial 980-nm pumps made for erbium-doped fiber amplifiers. Due to these and other features, this gain medium is being used in various applications.