Novel ultrafast parametric systems: high repetition rate single-pass OPG and fibre-feedback OPO

We describe two novel parametric systems for wavelength-tunable ultrashort pulse generation in the spectral range around 1.5 µm. We demonstrate the first single-pass optical parametric generator (OPG) that is directly pumped by a mode-locked laser at the full laser repetition rate of 35 MHz, obtaining up to 500 mW of average signal power with a pulse duration of 300 fs. We also report on a novel type of synchronously pumped high-gain optical parametric oscillator (OPO) with feedback through a single-mode fibre. We compare two fibre-feedback OPO systems, generating multi-watt average signal powers in 10 ps and 800 fs pulses. Both the OPG and fibre-feedback OPO system require a high parametric gain, which is achieved in periodically poled nonlinear crystals of LiNbO3 and LiTaO3, pumped with recently developed passively mode-locked all-solid-state lasers with very high average output power.