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FemtoLux 30 is a new 30 W femtosecond industrial grade laser build to work 24/7/365 without any interruptions. Other lasers of similar optical power use water for cooling, which means additional bulky and heavy water chiller is needed which require periodical maintenance (cooling system draining and rinsing, water and particle filter replacement). Moreover, in the unfortunate event of water leakage, not only laser head but also more expensive equipment could be damaged. FemtoLux 30 uses innovative direct refrigerant cooling method that do not contain any water inside the laser head and has much higher cooling efficiency. Laser cooling equipment is integrated together with the power supply unit into a single 4U rack mounted housing with a total weight of just < 15 kg. To tailor laser for specific applications, FemtoLux 30 laser has a tunable pulse duration from < 350 fs to 1 ps and can operate in very broad AOM controlled range of pulse repetition rate from a single shot to 4 MHz. While max energy of >250 µJ, that could be achieved while operating in a burst mode, could ensure higher ablation rates for different materials. FemtoLux 30 is designed as perfect tool for display and microelectronics manufacturing, as well as for micro processing and marking of brittle materials, such as glass, sapphire or ceramics, as well as for highest quality micro processing of different metals and polymers. Innovative laser control electronics ensures easy control of FemtoLux30, thus reducing time and resources required for integrating this laser into different equipment.

In this work, a double-pass end-pumped Yb:YAG amplifier system was investigated experimentally and numerically. The amplifier was seeded by a fibre-CPA based seed laser FemtoLux 30 (Ekspla). The presented laser system produced 129 W average power and 129 μJ energy pulses at 1 MHz pulse repetition rate, with optical-to-optical efficiency of 32% at room temperature (T = 20°C). The resulting beam quality was M² ∼ 2.1 and the measured depolarization losses were to 17.9%. After the compression, 441 fs pulse duration was achieved. During the work, comprehensive amplifier modelling was performed using the code written in Matlab. The modelling results matched well the experimental data, providing the tool to predict the performance of laser systems based on ytterbium-doped isotropic crystalline, ceramic and glass laser materials prior to designing and manufacturing.

We demonstrate a method to synthesize ultra-high repetition rate bursts of ultrashort laser pulses containing any number of pulses within a burst with identical pulse separation and adjustable amplitude. The key element to synthesize the GHz bursts of ultrashort laser pulses is an active fiber loop. The method was implemented in the fiber chirped pulse amplification system to obtain 72 nJ-energy bursts of 20 pulses with a 2.65 GHz intra-burst pulse repetition rate and a 500 kHz burst repetition rate. The dispersion compensation mechanism ensured a mean pulse duration of 570 fs within the bursts.