Fiber lasers are pumped by fibercoupled, multimode single chip devices at 915nm. That's what everybody assumes when asked for the type of fiber laser pumps and it was like this for many years. Coming up as an amplifier for telecom applications, the amount of pump power needed was in the range of several watts. Highest pump powers for a limited market entered the ten watts range. This is a range of power that can be covered by highly reliable multimode chips, that have to survive up to 25 years, e.g. in submarine applications. With fiber lasers entering the power range and the application fields of rod and thin disc lasers, the amount of pump power needed raised into the area of several hundred watts. In this area of pump power, usually bar based pumps are used. This is due to the much higher cost pressure of the industrial customers compared to telecom customers. We expect more then 70% of all industrial systems to be pumped by diode laser bars. Predictions that bar based pumps survive for just a thousand hours in cw-operation and fractions of this if pulsed are wrong. Bar based pumps have to perform on full power for 10.000h on Micro channel heat sinks and 20.000h on passive heatsinks in industrial applications, and they do. We will show a variety of data, "real" long time tests and statistics from the JENOPTIK Laserdiode as well as data of thousands of bars in the field, showing that bar based pumps are not just well suitable for industrial applications on high power levels, but even showing benefits compared to chip based pumps. And it's reasonable, that the same objectives of cost effectiveness, power and lifetime apply as well to thin disc, rod and slab lasers as to fiber lasers. Due to the pumping of fiber lasers, examples will be shown, how to utilize bars for high brightness fiber coupling. In this area, the automation is on its way to reduce the costs on the fibercoupling, similar to what had been done in the single chip business. All these efforts are part of the JENOPTIK Laserdiode's LongLifeTechnologie.

ARTEMIS, a multi-partner and multidisciplinary project, will be a users-dedicated facility that will provide ultrashort XUV pulses through high harmonic generation in a gas target. This high repetition rate synchronized source will allow new science in research fields spanning from the material science to the molecular physics and chemistry. The XUV radiation is expected to cover the range 10 -100 nm with an estimated photons flux up to 10 11 photons/s per harmonic. In this work we present the design and characterization of the monochromator that will be used in the beamline for the experiments requiring wavelength and bandwidth selection. The working principle is based on a plane grating operated at grazing incidence in the off-plane mount. This geometry has been selected because of the high diffraction efficiency, expected to be about 30%. To cover the entire spectral range four gratings can be selected which span over different regions and with different spectral resolution. When the appropriate grating is chosen, the wavelength scanning is performed by rotating the grating around an axis passing through the grating center and parallel to the grooves direction. The off-plane mount requires the grating to be used in collimated light, consequently the optical scheme is completed by two toroidal mirrors, the first in front of the source that collimates the XUV radiation before the grating and the second after the grating to focalize the spectrally dispersed photons on the exit slit. Using a single grating, the configuration is not time-delay-compensated, nevertheless the time broadening (depending on the source divergence, the wavelength, and the grating) is less than 50 fs.

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A novel infrared photothermal radiometric deep-level transient spectroscopy (PTR-DLTS) has been developed for semiconductor noncontact characterization and applied to GaAs wafer diagnostics. The technique is based on rate-window detection combined with wafer temperature ramping. Unlike other deep-level methodologies, PTR-DLTS should be easily implemented remotely for on-line or off-line impurity/electronic defect diagnostics and enjoys high spectral peak separation and spatial resolution limited only by the pump laser beam focus (≥1 μm). The impurity level in a Cr-compensated semi-insulating GaAs wafer has been detected at ∼375 K using the 514 nm line of an Ar+ laser. A Te-doped GaAs sample exhibited behavior consistent with photoinjected carrier lifetime enhancement due to surface state (trap) thermal filling at elevated temperatures.

In the recent years diode lasers have been established in many areas of industry and research. Especially the pumping of solid state lasers (DPSSL) is major field of application for high power diode lasers enabling solutions in many laser micro processes like cutting, sintering, structuring as well as drilling. This article reports progresses in the past as well as state of the art of high power diode lasers and describes their major applications.