Yb:CaF2 grown by liquid phase epitaxy

Ytterbium doped CaF2 crystalline layers have been grown for the first time from high temperature solutions at controlled atmosphere by using the liquid phase epitaxy technique. Doped layers having thicknesses between a few microns to a hundred of microns have been grown onto non-oriented and (1 1 1) oriented CaF2 substrates. The Yb3+:CaF2 layers show structural properties very close to the undoped substrate without any further thermal treatment. Registration of room temperature emission spectra and fluorescence lifetime measurements performed with epitaxial layers corresponding to different ytterbium concentrations show similar spectroscopic properties as in the bulk crystals.

► Growing of ytterbium-doped crystals by liquid phase epitaxy.
► The achieved crack-free epitaxial Yb:CaF2 layer thicknesses is higher than 50 μm.
► The maximum Yb3+ concentration to obtain free crack layers is estimated to be 5 mol%.
► Spectroscopy of the doped layers are similar to those of Yb:CaF2 bulk crystals.