High power mode comb from a non-collinear optic parametric oscillator

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For decades optic parametric oscillators (OPOs) are well known for producing femtosecond pulses with narrow bandwidth, acceptable average output powers, and wide tunability. In this project, we will explore novel concepts to access the few‐cycle pulse duration regime for the first time. Non‐collinear pumping geometry allows for ultra broadband gain bandwidth (we then call it NOPO). Adding a Kerr‐based fast saturable absorber in a second focus in combination with double‐chirped mirror based broadband dispersion management gives rise to the first few‐cycle pulses from an OPO. The main challenge will be the control of the intracavity pulse shaping dynamics to keep the ultrabroad spectrum in a long pulse for maximum gain extraction; our approach is based on ideas well elaborated in the context of fiber oscillators. In contrast to comparable laser oscillators, here the output power is only limited by the power of the pump laser due to the absence of thermal lensing effects. By pumping with a home‐built thin‐disk based femtosecond high power laser, we will approach the multi‐Watt level of average output power. The stable pulse train from the NOPO forms a broadband mode comb, which will be subject of in‐depth investigations regarding its coherence properties and timing jitter respectively. This very new concept for high power mode combs allows for efficient frequency conversion into remote wavelength regions, especially the near UV.