Exploring novel concepts and laser media for diode-pumped bulk lasers to tap new applications
Many novel industrial applications and laser matter interaction sciences are relying on high energy class lasers. Therefore, scaling the performance of such systems with respect to energy, repetition rate, and availability at other wavelengths is an essential point in laser development.
Over the last decades, diode pumped lasers based on neodymium doped active media became the state of the art for commercially available lasers. For further scaling of their performance, ytterbium doped active media are very attractive, due to their lower quantum defect, longer excited state lifetime and high quantum efficiency. Nevertheless, actually using these materials in such systems requires novel approaches for the laser architecture due to their relatively low cross sections. This includes simplified imaging multi-pass extraction schemes and modifications in resonator design to enable the use of unstable cavities for the direct generation of high energy pulses.
Materials doped with threefold positive thulium ions are a candidate to realize diode pumped high energy class laser systems in the wavelength range from 1.8 µm to 2 µm. So far detailed spectroscopic studies and first testbed systems are under development to define promising architectures for high energy short pulse systems.