Ternary colquiriite type fluorides as laser hosts

The Cr3+:LiCaAlF6 (Cr:LiCAF) and Cr3+:LiSrAlF6 (Cr:LiSAF) laser host crysta ls can be grown by the CZOCHRALSKI technique. Problems result from the evap oration of lithium-aluminium-fluorides during the growth process and a corr esponding stoichiometry shift of the melt towards the CaF2 (SrF2) corner of the ternary concentration triangle. Both Cr:LiCAF, and to a lower extend a lso Cr:LiSAF, contain micron-sized defects that disturb the lasing efficien cy heavily. The defects are assumed to be related to water and/or oxygen im purities within the starting materials and growth atmosphere and to peculia rities of the LiF - CaF2 - AlF3 ternary phase diagram.