Abstract:We present an ultrafast thin disk laser that generates an average output power of 275 W, which is higher than any other modelocked laser oscillator. It is based on the gain material Yb:YAG and operates at a pulse duration of 583 fs and a repetition rate of 16.3 MHz resulting in a pulse energy of 16.9 μJ and a peak power of 25.6 MW. A SESAM designed for high damage threshold initiated and stabilized soliton modelocking. We reduced the nonlinearity of the atmosphere inside the cavity by several orders of magnitude by operating the oscillator in a vacuum environment. Thus soliton modelocking was achieved at moderate amounts of self-phase modulation and negative group delay dispersion. Our approach opens a new avenue for power scaling femtosecond oscillators to the kW level. 435-453 (1996). 19201-19208 (2010). Huber, and U. Keller, "High-power ultrafast thin disk laser oscillators and their potential for sub-100-femtosecond pulse generation," Appl. Published in OpticsExpress 20, issue 21, 23535-23541, 2012 which should be used for any reference to this

No abstract

We present a semiconductor saturable absorber mirror mode-locked thin disk laser based on Yb:Lu(2)O(3) with an average power of 141 W and an optical-to-optical efficiency of more than 40%. The ideal soliton pulses have an FWHM duration of 738 fs, an energy of 2.4 microJ, and a corresponding peak power of 2.8 MW. The repetition rate was 60 MHz and the beam was close to the diffraction limit with a measured M(2) below 1.2.

No abstract

Ultrafast thin disk laser oscillators achieve the highest average output powers and pulse energies of any mode-locked laser oscillator technology. The thin disk concept avoids thermal problems occurring in conventional high-power rod or slab lasers and enables high-power TEM 00 operation with broadband gain materials. Stable and self-starting passive pulse formation is achieved with semiconductor saturable absorber mirrors (SESAMs). The key components of ultrafast thin disk lasers, such as gain material, SESAM, and dispersive cavity mirrors, are all used in reflection. This is an advantage for the generation of ultrashort pulses with excellent temporal, spectral, and spatial properties because the pulses are not affected by large nonlinearities in the oscillator. Output powers close to 100 W and pulse energies above 10 µJ are directly obtained without any additional amplification, which makes these lasers interesting for a growing number of industrial and scientific applications such as material processing or driving experiments in high-field science. Ultrafast thin disk lasers are based on a power-scalable concept, and substantially higher power levels appear feasible. However, both the highest power levels and pulse energies are currently only achieved with Yb:YAG as the gain material, which limits the gain bandwidth and therefore the achievable pulse duration to 700 to 800 fs in It is important to evaluate their suitability for power scaling in the thin disk laser geometry. In this paper, we review the development of ultrafast thin disk lasers with shorter pulse durations. We discuss the requirements on the gain materials and compare different Yb-doped host materials. The recently developed sesquioxide materials are particularly promising as they enabled the highest optical-tooptical efficiency (43%) and shortest pulse duration (227 fs) ever achieved with a mode-locked thin disk laser.

We report on a passively mode-locked Yb:YAG thin disk laser oscillator that generates 11.3-microJ pulses without the use of any additional external amplification. A repetition rate of 4 MHz is obtained using a 23.4-m-long multiple-pass cavity that extends the resonator length to a total of 37 m. The nearly transform-limited pulses at 45 W of average output power have a duration of 791 fs with a 1.56-nm-broad spectrum centered at 1030 nm. The laser is operated in a helium atmosphere to eliminate the air nonlinearity inside the resonator that previously limited the pulse energy.

High harmonic generation (HHG) of intense infrared laser radiation [1,2] enables coherent vacuum-UV (VUV) to soft-X-ray sources. In the usual setup, energetic femtosecond laser pulses are strongly focused into a gas jet, restricting the interaction length to the Rayleigh range of the focus. The average photon flux is limited by the low conversion efficiency and the low average power of the complex laser amplifier systems [3][4][5][6] which typically operate at kilohertz repetition rates. This represents a severe limitation for many experiments using the harmonic radiation in fields such as metrology or high-resolution imaging. Driving HHG with novel high-power diode-pumped multi-megahertz laser systems has the potential to significantly increase the average photon flux. However, the higher average power comes at the expense of lower pulse energies because the repetition rate is increased by more than a thousand times, and efficient HHG is not possible in the usual geometry. So far, two promising techniques for HHG at lower pulse energies were developed: external build-up cavities [7,8] and

No abstract