All-solid-state neodymium-based single-frequency master-oscillator fiber power-amplifier system emitting 5.5 W of radiation at 1064 nm

We demonstrate a master-oscillator fiber power-amplifier system consisting of a diode-pumped monolithic nonplanar ring oscillator as the master oscill ator and a Nd:glass double-clad fiber as the power amplifier. The system em its up to 5.5 W of single-frequency radiation at a wavelength of 1064 nm wi th an M-2 value of similar to 1.1. The optical emission spectrum is investi gated with respect to the background of residual amplified spontaneous emis sion. Spectrally resolved amplitude-noise behavior is examined. Further pow er-scaling possibilities are discussed. (C) 1999 Optical Society of America .