High-average-power 1.5-fs transform-limited laser system

Summary form only given.We present a high-average-power, all-diode-pumped laser system delivering ultrashort-pulse (15 fs), transform-limited output at 1-kHz repetition rate. The high-order spectral phase distortions that are usually present in the output of an amplifier system, and that lead to incomplete compression in the wings of the pulse, were eliminated by using a deformable mirror pulse shaper incorporated into the amplifier system. In past work, we demonstrated that the deformable mirror (DM) pulse shaper could compress the output from an oscillator. In this work we demonstrate that the DM has sufficient resolution to correct phase distortions in an amplifier system. Moreover, we demonstrate for the first time that transform-limited operation is possible from an amplifier system, and that spectral phase corrections increase the temporal contrast ratio of the pulse.