Dynamic focus shaping with mixed-aperture coherent beam combining.

A novel concept for dynamic focus shaping based on highly efficient coherent beam combining with micro-lens arrays (MLAs) as the combining element is presented. This concept allows us to control the power weights of diffraction orders by varying the absolute phases of an array of input beams. A proof-of-principle experiment is supported by simulations.

Thin-disk laser system operating above 10 kW at near fundamental mode beam quality.

We report on a thin-disk laser system with more than 10 kW of output power and a beam quality of =1.76 at an overall optical-to-optical efficiency of 51%. The system consists of two thin-disk laser oscillators and a thin-disk multi-pass amplifier system.

Coherent beam combining with micro-lens arrays.

A novel, to the best of our knowledge, concept for coherent beam combining is presented based on a simple setup with micro-lens arrays. These standard components are used in a proof-of-principle experiment for both coherent beam splitting and a combination of 5×5 beams. Here a combination efficiency above 90% is achieved.

Ultrafast green thin-disk laser exceeding 1.4 kW of average power.

We present an ultrafast laser with a near-diffraction-limited beam quality delivering more than 1.4 kW of average power in the visible spectral range. The laser is based on second harmonic generation in a lithium triborate crystal of a Yb:YAG thin-disk multipass amplifier emitting more than 2 kW of average power in the infrared.

Ultrafast thin-disk multi-pass amplifier system providing 1.9 kW of average output power and pulse energies in the 10 mJ range at 1 ps of pulse duration for glass-cleaving applications.

An ultrafast Yb-doped thin-disk multi-pass laser amplifier system with flexible parameters for material processing is reported. We can generate bursts consisting of four pulses at a distance of 20 ns and a total energy of 46.7 mJ at a repetition rate of 25 kHz.

Ultrafast thin-disk multipass laser amplifier delivering 1.4 kW (4.7 mJ, 1030 nm) average power converted to 820 W at 515 nm and 234 W at 343 nm.

We report on an Yb:YAG thin-disk multipass laser amplifier delivering sub-8 ps pulses at a wavelength of 1030 nm with 1420 W of average output power and 4.7 mJ of pulse energy. The amplifier is seeded by a regenerative amplifier delivering 6.

1.1 kW average output power from a thin-disk multipass amplifier for ultrashort laser pulses.

We report on a thin-disk multipass amplifier for ultrashort laser pulses delivering an average output power of 1105 W. The amplifier was seeded by a Trumpf TruMicro5050 laser with a power of 80 W at a wavelength of 1030 nm, pulse duration of 6.5 ps, and repetition rate of 800 kHz.

Mode-locked Yb:YAG thin-disk oscillator with 41 µJ pulse energy at 145 W average infrared power and high power frequency conversion.

We demonstrate the generation of 1.1 ps pulses containing more than 41 µJ of energy directly out of an Yb:YAG thin-disk without any additional amplification stages. The laser oscillator operates in ambient atmosphere with a 3.

Improving the brightness of a multi-kilowatt single thin-disk laser by an aspherical phase front correction.

We report on results obtained with an aspherical mirror to compensate for the phase front aberrations of a cw thin-disk laser with a single disk in the resonator. A record output power of 5 kW with a beam quality suitable for laser cutting (beam propagation factor M2=9.2) has been achieved.

High-repetition-rate picosecond pump laser based on a Yb:YAG disk amplifier for optical parametric amplification.

We report an optically synchronized picosecond pump laser for optical parametric amplifiers based on an Yb:YAG thin-disk amplifier. At 3 kHz repetition rate, pulse energies of 25 mJ with 1.6 ps pulse duration were achieved with an rms fluctuation in pulse energy of <0.

Subpicosecond thin-disk laser oscillator with pulse energies of up to 25.9 microjoules by use of an active multipass geometry.

The pulse shaping dynamics of a diode-pumped laser oscillator with active multipass cell was studied experimentally and numerically. We demonstrate the generation of high energy subpicosecond pulses with a pulse energy of up to 25.9 microJ at a pulse duration of 928 fs directly from a thin-disk laser oscillator.

Passively mode-locked Yb:YAG thin-disk laser with pulse energies exceeding 13 microJ by use of an active multipass geometry.

We demonstrate the generation of high-energy picosecond pulses directly from a thin-disk laser oscillator by employing a self-imaging active multipass geometry. Stable single-pulse operation has been obtained with an average output power in excess of 50 W, excluding a cw background of 8%, at a repetition rate of 3.8 MHz.

Generation of few-cycle pulses directly from a MHz-NOPA.

We demonstrate the generation of 10-fs-pulses from a noncollinear optical parametric amplifier (NOPA). The NOPA is driven by microjoule pulses from a directly diode pumped Yb:KYW oscillator with cavity-dumping.

Megahertz optical parametric amplifier pumped by a femtosecond oscillator.

We demonstrate, for the first time to our knowledge, an optical parametric amplifier directly pumped by a femtosecond oscillator. Wavelength-tunable pulses in the ranges 0.65-0.

High-peak-power pulses from a cavity-dumped Yb:KY(WO4)2 oscillator.

We report generation of 1.35 microJ femtosecond laser pulses with a peak power of 3 MW at 1 MHz repetition rate from a diode-pumped Yb:KY(WO4)2 laser oscillator with cavity dumping. By extracavity compression with a large-mode-area fiber and a prism sequence, we generate ultrashort pulses with a duration of 21 fs and a peak power of 13 MW.

High speed electro-optical cavity dumping of mode-locked laser oscillators.

High speed electro-optical cavity dumping is demonstrated with diode-pumped mode-locked laser oscillators, namely a femtosecond Yb:glass and a picosecond Nd:YVO4 oscillator. Repetition frequencies exceeding 1MHz are obtained with pulse energies of more than 300nJ /1 microJ. Being compact and easy to operate light sources, these laser systems open up various scientific and industrial applications.

Diode-pumped, ultrafast, multi-octave supercontinuum source at repetition rates between 500 kHz and 20 MHz using Yb:glass lasers and tapered fibers.

We present a compact, all diode-pumped supercontinuum source based on a SESAM mode-locked Yb:glass oscillator at 1040 nm and a tapered fiber. The oscillator has a repetition rate of 20 MHz, a pulse duration of 200 fs, and a maximum pulse energy of about 15 nJ. This system delivers an 1100 nm broad spectrum with an output power of more than 100 mW.

Er:Yb-doped waveguide laser fabricated by femtosecond laser pulses.

Laser action is demonstrated in a 20-mm-long waveguide fabricated on an Er:Yb-doped phosphate glass by femtosecond laser pulses. An output power of 1.7 mW with approximately 300 mW of pump power coupled into the waveguide is obtained at 1533.

Optical waveguide writing with a diode-pumped femtosecond oscillator.

Optical waveguide writing is demonstrated by means of a diode-pumped cavity-dumped Yb:glass femtosecond laser oscillator with a pulse energy of 270 nJ at a 166-kHz repetition rate. Waveguides realized on an Er:Yb-doped phosphate glass are almost perfectly mode matched to standard single-mode fibers at 1.55 microm and show a 1.

Solitary pulse shaping dynamics in cavity-dumped laser oscillators.

The pulse shaping dynamics of a diode-pumped laser oscillator with cavity dumping operating in the solitary regime is studied experimentally and numerically. The stability of the laser system is investigated in dependence on the relevant laser parameters. With a stroboscopic detection technique the intracavity temporal and spectral pulse profiles are measured between two dumping events.

Period doubling and deterministic chaos in continuously pumped regenerative amplifiers.

Multi-energy and chaotic pulse energy output from a continuously pumped regenerative amplifier is observed for dumping rates around the inverse upper state lifetime of the gain medium. The relevant regimes of operation are analyzed numerically and experimentally in a diode-pumped Yb:glass regenerative amplifier. The boundaries between stable and unstable pulsing are identified and stability criteria in dependence on the amplifier gate length and pump power are discussed.