abstract
High-quality potassium tantalate (KTaO3, KT) single crystals are grown by a high-temperature self-flux solution modified method in which potassium carbonate (K2CO3) and boron oxide (B2O3) are utilized as a complex flux. Additions of small amounts of boron oxide, used because of its low melting temperature (450 degrees C) and tendency to decrease the weight losses, increased the metastable region, requiring lower temperature (<= 1300 degrees C) for the growth of relatively large KT crystals thereby suppressing the K volatilization tendency. By changing the flux composition and flux to solute proportion growth conditions are modified. The as-grown potassium tantalate crystals exhibit a dielectric permittivity of 6600 and dielectric losses of 0.004 at 13 K and 100 kHz. These results suggest a new promising approach for growing relatively large size and high quality single crystals within KT-based system.
keywords
POTASSIUM TANTALATE; RESONANCE; SRTIO3
subject category
Chemistry; Crystallography; Materials Science
authors
Zlotnik, S; Vilarinho, PM; Costa, MEV; Moreira, JA; Almeida, A
our authors
Isabel Margarida Miranda Salvado
Associate Professor
Maria Elisabete Jorge Vieira Costa
Collaborator
Paula Maria Lousada Silveirinha Vilarinho
Vice Director
Sebastian Zlotnik
Post-doc FellowshipGroups
G2 - Photonic, Electronic and Magnetic Materials
G5 - Biomimetic, Biological and Living Materials
acknowledgements
The authors are thankful to Prof. Ian Reaney for TEM characterizations. This work was funded by FCT under the project PTDC/CTM/64805/2006 and FEDER.