Teilprojekt 9



Besides administrative aspects, the coordination project of the research unit includes a Mercator module with the central objective to investigate the electronic point defect structure in lithium niobate-lithium tantalate solid solutions (LNT) by optical spectroscopy. Special aspects are the investigations under in-situ conditions at high temperatures and defined oxygen partial pressures. Thereby, it has to be figured out whether the three types of polaron identified in lithium niobate (LN) exist stably in Ta-containing solid solutions and especially at high temperatures. Further emphasis is put on the investigation of chemical diffusion, the nature and temperature dependence of the optical absorption band edge, and the dependence of the Fe2+/Fe3+ ratio in Fe-doped LNT on temperature and oxygen partial pressure.

The Mercator module is carried out in close cooperation with Prof. K.-D. Becker (co-leader of the research unit, University of Braunschweig) and the research groups of Prof. S. Ubizskii and Dr. D. Sugak (both Lviv Polytechnic National University, Ukraine).

Furthermore, Prof. G. Borchardt (co-leader of the research group, Clausthal University of Technology) actively supports the research work in the field of ion transport, which is located predominantly in sub-project 2.

Project managers and employees

Prof. Dr. H. Fritze
Tanja Kuhfuß