| Abstract [eng] |
Rapidly developing areas of high field physics, generation of high order harmonics or isolated attosecond pulses, require high peak power few-cycle pulse sources. Optical parametric chirped pulse amplification (OPCPA) has shown potential to satisfy these requirements and at present OPCPA is the leading technology for high energy few-cycle pulse table-top systems. The main objectives of this thesis were to investigate optical parametric amplification of broadband seed pulses in femtosecond and picosecond regimes, to develop and optimize a compact TW-scale OPCPA system intended for various applications in areas of high-field physics. In this thesis the main concept of such system is discussed, advantages and disadvantages of proposed approach are analyzed, the setup is compared to other world known systems. In this thesis an original approach for power scaling of regenerative amplifier by implementing several active elements in prolonged resonator has been proposed and investigated. Femtosecond pulse amplification in dual active element Yb:KGW regenerative amplifier has been demonstrated, resulting in boost of average output power to 30 W. Broad bandwidth pulse generation, parametric amplification and compression to transform limited values were analyzed both numerically and experimentally. White light continuum generation in bulk material for broadband seed formation, its further optical parametric amplification in noncollinear scheme were investigated and Yb:KGW driven setup was developed, allowing for generation of 20 microjoule energy output pulses at 800 nm central wavelength, which were compressed to sub-10 fs duration. Also, spatio-temporal distortions of chirped signal pulse appearing due to not-matched pulse fronts in non-collinear parametric amplifier have been investigated and it has been shown, mainly spatial chirp occurred under given conditions, whereas angular dispersion of the amplified pulse remained negligible. Results on broad bandwidth pulse amplification in optical parametric amplifier pumped by ~200 mJ picosecond pulses are presented. Output energy of 30 mJ was achieved and the bandwidth of amplified pulse spectrum supports the pulse compression to sub-10 fs durations. Such parameters correspond to ~3 TW pulse peak power. The concept of stepwise increase of pulse duration in multistage optical parametric amplification stages is proposed and employed, optimizing in this way the seed pulse intensities in amplification stages and providing route for output pulse energy contrast enhancement. |
