P. Weßels
S. Unland
R. Kalms
S. Spiekermann
I. Balasa
H. Mädebach
S. Kramprich
L. Jensen
D. Kracht
M. Lorrai
P. G. Lorrai
M. Hmidat
J. Butkus
L. Lukoševičius
J. Neumann

GALACTIC - High Performance Alexandrite Crystals and Coatings for High Power Space Applications

International Conference on Space Optics (ICSO)
30. März - 02. April
Type: Konferenzbeitrag
Spaceborne earth observation based on laser instruments provides new technologies to monitor the atmosphere or the planet’s surface. Recent examples of laser systems rely on Nd:YAG laser technology and have shown the challenge to combine the different requirements for space applications. High optical efficiencies and a tunable wavelength, which are desirable for many applications, have to be reconciled with a laser design as simple as possible. Space qualified Alexandrite laser crystals can address all these current issues. It is an inherently tunable material and has high optical efficiency due to the small quantum defect. Furthermore, it requires only a single wavelength conversion step to reach the UV wavelength region. A major drawback of Alexandrite laser technology is currently the European non-dependence status as the Alexandrite market is being dominated by US based companies. The Horizon 2020 project GALACTIC, which will be presented, has been initiated to realize space qualified high quality, high performance coated Alexandrite crystals rest on a purely European-based supply chain. The project consortium, consisting of Optomaterials S.r.l., Altechna Coatings and the Laser Zentrum Hannover e.V., provides the necessary expertise in the fields of laser crystal growth, optical coatings and laser systems to push the development of high quality, high damage threshold Alexandrite coatings within the EU up to TRL 6. In order to reach the GALACTIC goals, different technology areas will be addressed. On the one hand, Optomaterials S.r.l. as an experienced optical crystal manufacturer will continuously refine the crystal growth process and improve the raw crystals as well as the cutting and polishing quality step-by-step. As an experienced company in optical coatings production for space applications, Altechna Coatings will secondly develop high quality, low loss, high damage threshold coatings specifically tailored for application onto Alexandrite laser crystals. The superior performance of the coated crystals will then be proven in demonstrator laser systems. The Laser Zentrum Hannover e.V. has the required knowledge to set up laser demonstrator prototypes, whose specifications mimic typical earth observation laser source requirements. Finally, the GALACTIC consortium will work closely together to characterize and qualify the developed coated laser crystals. By collaborating with the European space industry and deriving the detailed requirements from typical earth observation space missions, a detailed TRL 6 components test plan will prove the TRL 6 qualification of the developed coated laser crystals. This will conclude the development process and will enhance the European non-dependence status of the Alexandrite laser crystal market. At the conference, we will present the project and its consortium as well as detailed strategies to enable a non-dependence of Europe on coated Alexandrite laser crystal technology and enabling long term European availability of this technology. This project has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No 870427.