Compact 1-W Yb-doped double-cladding fiber amplifier using V-groove side-pumping

A compact packaged fiber amplifier was constructed using a Yb-doped double-cladding fiber, which was V-groove side-pumped by a laser diode operating at 975 nm. Under saturation, the amplifier generated 1 W at 1064 nm. The small-signal gain reached a maximum of 50 dB at 1075 nm and was greater than 40 dB in the range of 1042-1093 nm.