Peak-power scaling of femtosecond SESAM-modelocked Yb: Lu₂O₃ thin-disk lasers

Ultrafast laser sources are opening new industrial and scientific applications. In particular, SESAM-modelocked thin-disk laser (TDL) oscillators are promising candidates to replace complex amplifier systems by compact high-power oscillators combining high pulse energy and MHz repetition rate. Record-high average powers up to 275 W and peak powers up to 66 MW have been achieved with SESAM-modelocked Yb:YAG TDLs [1]. However, reducing the pulse duration to sub 200 fs while simultaneously increasing the peak power of SESAM-modelocked TDLs remains an ongoing challenge. The sesquioxide Yb:Lu 2 O 3 (Yb:LuO) is a potentially ideal candidate material as it combines a broad emission bandwidth and a high thermal conductivity [2]. Earlier Yb:LuO TDL results include average powers up to 140 W (740 fs) or pulse durations down to 140 fs (7 W), in all cases at moderate peak powers <;3 MW [1]. Further femtosecond power scaling requires the development of large-area SESAMs with improved thermal properties and high surface flatness, enabled by our new SESAM bonding technique [3].