Amplification of ultrashort pulses

We present an extremely compact ultrafast solid-state laser amplifier at 1030 nm for material processing applications. We designed a diode side-pumped planar waveguide amplifier to provide high gain and gain uniformity in the crystal. We reduced parasitic oscillations caused by amplified spontaneous emissions by choice of seed beam shape and intensity, multi-pass mirror configuration and crystal design. Power amplification results up to a 5-pass amplifier are discussed.