Soliton self-compression and spectral broadening of 1 μm femtosecond pulses in single-domain KTiOPO₄

Summary, in English

Efficient, diode-pumped high energy femtosecond laser systems around 1 μm based on Yb-gain media are readily commercially available. However, owing to the gain bandwidth limitations, the pulses generated in such lasers are substantially longer than the ones generated in Ti:Sapphire systems. A simple, energy-scalable pulse self-compression scheme for the pulses around 1 μm thus would be of great interest for many applications, including time-resolved pump-probe spectroscopy, high-harmonics generation, etc. The self-phase modulation during nonlinear propagation in filaments in gasses is often employed for pulse self-compression [1,2]. Such schemes typically require rather bulky setups and careful control of group velocity dispersion. Some years ago it has been shown theoretically that Raman-active molecules in gaseous form could be used for mid-infrared pulse compression [3].