Power scaling of ytterbium INNOSLAB amplifiers beyond 100W average power

The Innoslab design, already established for neodymium doped laser materials, was applied to ytterbium doped laser materials. Recent progresses in brightness of high power diode lasers facilitate efficient pumping of quasi-three-level laser materials. A compact diode-pumped Yb:YAG Innoslab fs-oscillator-amplifier system, scalable to the kilowatt range, was realized. Nearly transform and diffraction limited 682 fs pulses at 400W average output power and 76 MHz repetition rate at room temperature and without using CPA technique have been achieved so far.