In the framework of the Laser Lightning Rod project, whose aim is to show that laser-induced filaments can guide lightning discharges over considerable distances, we study over a distance of 140 m the filaments created by a laser system with J-range pulses of 1 ps duration at 1 kHz repetition rate. We investigate the spatial evolution of the multiple filamentation regime using the fundamental beam at 1030 nm or using combination with the second and third harmonics. The measurements were made using both a collimated beam and a loosely focused beam.

We present an ultrafast thin-disk based multipass amplifier operating at a wavelength of 1030 nm, designed for atmospheric research in the framework of the Laser Lightning Rod project. The CPA system delivers a pulse energy of 720 mJ and a pulse duration of 920 fs at a repetition rate of 1 kHz. The 240 mJ seed pulses generated by a regenerative amplifier are amplified to the final energy in a multipass amplifier via four industrial thin-disk laser heads. The beam quality factor remains ∼ 2.1 at the output. First results on horizontal long-range filament generation are presented.

TRUMPF Scientific Lasers provides ultrafast laser sources for the scientific community with high pulse energies and high average power. All systems are based on the industrialized TRUMPF thin-disk technology. Regenerative amplifiers systems with multi-millijoule pulses, kilohertz repetition rates and picosecond pulse durations are available. Record values of 220mJ at 1kHz could be demonstrated originally developed for pumping optical parametric amplifiers. The ultimate goal is to combine high energies, <100mJ per pulse, with average powers of several hundred watts to a kilowatt. Based on a regenerative amplifier containing two Ytterbium doped thin-disks operated at ambient temperature pulses with picosecond duration and more than 100mJ could be generated at a repetition rate of 10kHz reaching 1kW of average output power. This system is designed to operate at different repetition rates from 100kHz down to 5kHz so that even higher pulse energies can be reached. This type of ultrafast sources uncover new application fields in science. Laser based lightning rods, X-ray lasers and Compton backscatter sources are among them.

Today thin-disk lasers routinely provide high pulse energies at picosecond pulse durations and kHz repetition rates. Systems with more than 200mJ per pulse are commercially available. After the introduction of the Dira 200-1, providing 200mJ at 1kHz, TRUMPF Scientific Lasers complements its thin-disk regenerative amplifier product portfolio by systems with a few hundred Watts of average output power. Still based on a single disk a flexible laser system with more than 500W was realized. Originally, it was designed for a 50kHz operation, delivering 10mJ pulses, but it also can be set-up for different repetition rates like 10kHz or 100kHz. TRUMPF Scientific Lasers regenerative amplifiers show an excellent long-term performance. The 500W system has a power stability of 0.5%.Scientific applications often require higher average output powers, even with high pulse energies. Based on the extensive experience with highest average power continuous wave laser systems by TRUMPF a more powerful regenerative amplifier system is currently under development by TRUMPF Scientific Lasers. This laser uses two disk laser heads inside the same cavity to provide more than 1kW average output power. First results show an average power of more than 1kW at repetition rates of 10kHz and higher. A pulse duration below 1ps could be reached.

A thin-disk based regenerative amplifier with a compressed output power of more than 1 kW is presented. At a wavelength of 1031 nm pulse energies ≥100 mJ are demonstrated at a repetition rate of 10 kHz with pulse durations of <1.0 ps.

We report on the latest developments at TRUMPF Scientific Lasers in the field of ultra-short pulse lasers with highest output energies and powers. All systems are based on the mature and industrialized thin-disk technology of TRUMPF. Thin Yb:YAG disks provide a reliable and efficient solution for power and energy scaling to Joule-and kW-class picosecond laser systems. Due to its efficient one dimensional heat removal, the thin-disk exhibits low distortions and thermal lensing even when pumped under extremely high pump power densities of 10kW/cm(2). Currently TRUMPF Scientific Lasers develops regenerative amplifiers with highest average powers, optical parametric amplifiers and synchronization schemes. The first few-ps kHz multi-mJ thin-disk regenerative amplifier based on the TRUMPF thin-disk technology was developed at the LMU Munich in 2008(1). Since the average power and energy have continuously been increased, reaching more than 300W (10kHz repetition rate) and 200mJ (1kHz repetition rate) at pulse durations below 2ps. First experiments have shown that the current thin-disk technology supports ultra-short pulse laser solutions >1kW of average power.Based on few-picosecond thin-disk regenerative amplifiers few-cycle optical parametric chirped pulse amplifiers (OPCPA) can be realized. These systems have proven to be the only method for scaling few-cycle pulses to the multi-mJ energy level. OPA based few-cycle systems will allow for many applications such as attosecond spectroscopy, THz spectroscopy and imaging, laser wake field acceleration, table-top few-fs accelerators and laser-driven coherent X-ray undulator sources.Furthermore, high-energy picosecond sources can directly be used for a variety of applications such as X-ray generation or in atmospheric research.

A thin-disk based regenerative amplifier with a compressed output power of more than 540 W is presented. Energies ≥10 mJ are demonstrated at 50 kHz with durations <1.2 ps. Further preliminary scaling at 5 kHz led to 900 W of average power before compression.

We report on a chirped-pulse regenerative thin-disk amplifier generating 220 mJ pulse energy at 1 kHz repetition rate with a pulse duration of 1.9 ps for pumping few-cycle optical parametric amplifiers (OPA).

An OPCPA system with 15 W of average power at 300 kHz repetition rate generating CEP-stable few-cycle pulses is presented. The system exhibits pulse durations below 6 fs, a peak power of 4.5 GW and an excellent long-term performance over hours of operation with power fluctuations of less than 1.5%.

We demonstrate a highly efficient regenerative amplifier containing a single thin-disk gain medium delivering 220mJ of pulse energy at 1 kHz repetition rate with a pulse duration of 1.9 ps. The laser system consists of a seed laser, stretcher, regenerative amplifier resonator containing a single thin-disk and a compressor. The seed pulses are delivered by a commercial fiber oscillator emitting ~2 nJ pulses with a spectral bandwidth of 40 nm centered at 1030 nm.

We report on a CEP-stable OPCPA system reaching multi-GW peak powers at 300 kHz repetition rate. It delivers 15 W of average power, over 50 µJ of compressed pulse energy and a pulse duration below 6 fs. By implementing an additional pump-seed-synchronization, the output parameters are stabilized over hours with power fluctuations of less than 1.5%.

In the original manuscript, a residual RMS timing jitter below 2 fs between pump and seed pulses in the stabilized case was claimed. Following a reevaluation of the data, this was underestimated. Due to a rounding error in the calibration routine, a miscalculated calibration factor was extracted. By using a higher precision, the updated residual timing jitter amounts to 2.76 fs, or sub-3 fs. In this erratum, the calibration routine is briefly reviewed and Fig. 4, which presents the timing jitter in the stabilized and unstabilized case, is updated. All other results remain unaffected.

Short-pulse-pumped optical parametric chirped pulse amplification (OPCPA) demands powerful picosecond lasers with high average powers and high pulse energies. We report on the current picosecond thin-disk amplifiers development and their applications in research.

We present a 300 W picosecond thin-disk based pump laser designed for amplifying few-cycle pulses by means of optical parametric amplification (OPA). Output energies up to 30 mJ are demonstrated at 10 kHz with a pulse duration of 1.6 ps.