1.4-W red generation by frequency mixing of seeded Yb and Er fiber amplifiers

Synchronous seeding of kW peak, 10 W average power Yb and Er fiber amplifiers is proposed and used for sum-frequency generation of 1.4-W average power at 630 nm in periodically poled potassium titanyl phosphate (PPKTP). The potential of scalability to 3-4 W average power in the red is discussed.