We present a high peak and average power optical parametric chirped pulse amplification system driven by diode-pumped Yb:KGW and Nd:YAG lasers running at 1 kHz repetition rate. The advanced architecture of the system allows us to achieve >53 W average power combined with 5.5 TW peak power, along with sub-220 mrad CEP stability and sub-9 fs pulse duration at a center wavelength around 880 nm. Broadband, background-free, passively CEP stabilized seed pulses are produced in a series of cascaded optical parametric amplifiers pumped by the Yb:KGW laser, while a diode-pumped Nd:YAG laser system provides multi-mJ pump pulses for power amplification stages. Excellent stability of output parameters over 16 hours of continuous operation is demonstrated.

The extreme light infrastructure attosecond light pulse source offers beamtime for users of various attosecond and particle sources driven by versatile laser systems. Here we report on the state of the art of a few-cycle, multi-TW, 1kHz repetition rate laser system, now fully operational in the facility. The system is based on four stages of optical parametric amplifiers (OPAs) pumped by a total of 320mJ, 80ps frequency-doubled Nd:YAG laser pulses. All OPA stages utilize double crystal configuration, which design has been also confirmed by model calculations. The 1kHz SYLOS 2 system produces 32mJ laser pulses around a central wavelength of 891nm with 6.6fs (<2.3 optical cycles) pulse duration exceeding the peak power of 4.8 TW on a daily basis. The recorded best pulse duration is 6.3fs, which corresponds to 2.12 cycles and 5.1 TW peak power. During long-term (24h) performance tests, energy stability of 1.2%, carrier-envelope phase (CEP) stability of 210mrad, and pointing stability of 0.4µrad were demonstrated, while the Strehl ratio of the beam is kept above 0.75. In order to help the alignment of all the different experiments at the facility and to reduce the workload on SYLOS 2 system, a second laser system has been developed. The so-called SYLOS Experimental Alignment (SEA) laser mimicks the performance of the SYLOS 2 laser, but at a repetition rate two orders of magnitude lower and without CEP-stabilization. The three single-crystal OPA stages of the SEA laser provide 42mJ pulse energy for the users, while having energy stability of 0.87% and sub-13fs pulse duration at a repetition rate ranging from a single shot up to 10Hz.

We present a compact TW-class OPCPA system operating at 800 nm. Broadband seed pulses are generated and pre-amplified to 25 μJ in a white light continuum seeded femtosecond NOPA. Amplification of the seed pulses to 35 mJ at a repetition rate of 10 Hz and compression to 9 fs is demonstrated.

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We present implementation of the energy-efficient and flexible laser beam shaping technique in a high-power and high-energy laser amplifier system. The beam shaping is based on a spatially variable wave plate (SVWP) fabricated by femtosecond laser nanostructuring of glass. We reshaped the initially Gaussian beam into a super-Gaussian (SG) of the 12th order with efficiency of about 50%. The 12th order of the SG beam provided the best compromise between large fill factor, low diffraction on the edges of the active media, and moderate intensity distribution modification during free-space propagation. We obtained 150 mJ pulses of 532 nm radiation. High-energy, pulse duration of 85 ps and the nearly flat-top spatial profile of the beam make it ideal for pumping optical parametric chirped pulse amplification systems.