Growth of Al doped Ca3TaGa3Si2O14 piezoelectric single crystals with various Al concentrations

• All as-grown crystals were identified as a single phase of langasite type structure.
• The lattice parameters systematically decreased with increase in Al concentration.
• Actual Al compositions in the crystals were almost the same as the nominal compositions.

Al-doped Ca3TaGa3Si2O14 single crystals with various Al concentrations were grown by the micro-pulling-down method and their structure and chemical composition were investigated. Ca3Ta(Ga1−xAlx)3Si2O14 crystals with x=0, 0.2, 0.4, 0.6, 0.8 and 1 were grown. They were highly transparent and a single phase of langasite-type structure was confirmed in the powder X-ray diffraction measurement. Their lattice parameters related to the a- and c-axes systematically decreased with increase in Al concentration. It followed from the EPMA analysis that the real Al concentration in the crystals almost corresponded to the nominal compositions.