A new class of ordered langasite structure compounds

Author

Chai, B.H.T. ; Bustamante, A.N.P. ; Chou, M.C.

Author_Institution

Crystal Photonics Inc., Sanford, FL, USA

fYear

2000

fDate

2000

Firstpage

163

Lastpage

168

Abstract

Langasite (LGS) and its isomorphs are only a few piezoelectric crystals which have the unique temperature compensation property. But most of the known langasite structure compounds are disordered. Disorder causes higher acoustic losses and also nonuniform mechanical properties. We reported a new class of langasite isomorph which has all the cations totally ordered. They are CNGS (Ca₃NbGa₃Si₂O₁₄), CTGS (Ca₃TaGa₃Si₂O₁₄), SNGS (Sr ₃NbGa₃Si₂O₁₄) and STGS (Sr ₃TaGa₃Si₂O₁₄). They all melt congruently. High quality single crystals were produced by Czochralski melt pulling technique. They have the advantages of low Ga₂O ₃ content, high acoustic velocity and low acoustic loss

Keywords

calcium compounds; crystal growth from melt; crystal structure; gallium compounds; isomorphism; lattice constants; niobium compounds; piezoelectric materials; strontium compounds; surface acoustic waves; tantalum compounds; Ca₃NbGa₃Si₂O₁₄; Ca₃TaGa₃Si₂O₁₄; Czochralski melt pulling technique; SAW velocity; Sr₃NbGa₃Si₂O₁₄; Sr₃TaGa₃Si₂O₁₄; crystal structure; high acoustic velocity; high quality single crystals; langasite isomorphs; lattice constants; low Ga₂O₃ content; low acoustic loss; ordered langasite structure compounds; piezoelectric crystals; temperature compensation property; totally ordered cations; Acoustic materials; Acoustic waves; Chemicals; Crystalline materials; Gallium arsenide; Material properties; Mechanical factors; Photonic crystals; Surface acoustic waves; Temperature;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control Symposium and Exhibition, 2000. Proceedings of the 2000 IEEE/EIA International

Conference_Location

Kansas City, MO

ISSN

1075-6787

Print_ISBN

0-7803-5838-4

Type

conf

DOI

10.1109/FREQ.2000.887346

Filename

887346