Compact diode-pumped 11 kW Yb:YAG Innoslab femtosecond amplifier

Abstract

We demonstrate a compact diode-pumped Yb:KGW femtosecond oscillator-Yb:YAG Innoslab amplifier master oscillator power amplifier (MOPA) with nearly transform-limited $636\mathrm{fs}$ pulses at $620\mathrm{W}$ average output power, $20\mathrm{MHz}$ repetition rate, and beam quality of ${M_x}^2=1.43$ and ${M_y}^2=1.35$. By cascading two amplifiers, we attain an average output power of $1.1\mathrm{kW}$, a peak power of $80\mathrm{MW}$, and a $615\mathrm{fs}$ pulse width in a single linearly polarized beam. The power-scalable MOPA is operated at room temperature, and no chirped-pulse amplification technique is used.