Abstract

Ultrahigh power 1.5-μm fiber amplifiers have applications in large-passive split fiber architectures, long-distance repeater-less links, satellite communication links, nonlinear optical switching, laser radar, and remote sensing. The output power of fiber amplifiers has previously been limited by the amount of diffraction-limited power from diode laser sources. Pumping by diffraction-limited MOPA semiconductor sources has been demonstrated/however the power scalability of these sources and the difficulty of single-mode fiber coupling are significant disadvantages of this approach.¹ We employ cladding-pumped fiber lasers as the pump source because single-mode fiber-coupled output powers of 5 W are obtainable from a single diode-pumped source.² The output of these Nd³⁺ cladding-pumped lasers is at 1.06 μm, necessitating the use of Er/Yb co-doped optical fibers as the gain medium.³

© 1996 Optical Society of America