Motivation
The project aims at growing new or unconventional crystals for enhanced optical or magneto-optical properties. In this project, Rare-Earth (such as RE: Yb3+, Er3+, Tm3+ or Tb3+) doped or co-doped fluoride and oxide matrix will be investigated. Based on the expertise of the project director and that of the West University of Timisoara (WUT), rare earth sesquioxides RE2O3 (RE= Y, Gd, Lu), CaF2 and BaF2 crystals will be grown and investigated. In addition, new promising defined compounds or solid solutions such as KY3F10-KTb3F10 (KYF-KTF) will be grown with various dopant concentrations.
Suitable pulling techniques (Czochralski, Bridgman, flux methods) will be chosen with respect to the chemical behavior of selected compositions. At the same time, numerical modelling will be investigated for the optimization of the different growth processes and the setting of the suitable thermal environment.
On the one hand, single crystals will be grown for laser and luminescent applications by simple doping (few mol. % of Tb3+, Tm3+) or by co-doping (few mol.% Yb3+/Er3+) by the mean of up-conversion phenomenon, in order to reach new wavelengths in the visible range (green, yellow) and in the mid-infra-red range (1.5µm-2.3µm). On the other hand, large Tb3+ cation substitution large content (few tens of mol.%), up to 100 mol.%, will be investigated in order to characterize the Faraday rotation and the Verdet constant in both rare earth sesquioxides and KTF-based matrix. Stability of the Tb-based solid solution molar range will be investigated with different other RE-cation contents in the crystalline matrix (Y, Gd).
All these research activities will help in the development of a Centre of Excellence in the field of crystal growth, leading to a world-wide recognition of the expertise and the importance of the crystals grown in WUT crystal growth laboratory.