GROWTH-CONDITIONS AND COMPOSITION OF SRPRCAO4 SINGLE-CRYSTALS

The clarification of the crystallization behaviour allowed for the fir st time growth of optically homogeneous SrPrGaO4 single crystals by th e Czochralski technique. They were found to melt incongruently at 1462 degrees C. The composition of the starting melt deviates from the int egral stoichiometry to a higher gallium and lower strontium content. D ue to the K2NiF4 structure and their lattice constants of a = 0.3813(2 ) nm and c = 1.2532(6) nm these crystals are promising candidates as s ubstrate material for high-T-c superconductor thin films. A super stru cture was observed in SrPrGaO4. The same type of superstructure was de tected in SrLaGaO4 single crystals as well.