Crystal growth of strontium barium niobate BaxSr1−xNb2O6
| Autor: | G. Desplanches, P. Margotin, Claude Brehm, Jean-Yves Boniort, J.-Y. Barraud |
|---|---|
| Rok vydání: | 1975 |
| Předmět: |
Strontium
Materials science chemistry.chemical_element Barium Crystal growth Strontium barium niobate Condensed Matter Physics Inorganic Chemistry chemistry.chemical_compound Crystallography Tetragonal crystal system chemistry Phase (matter) Materials Chemistry Single crystal Monoclinic crystal system |
| Zdroj: | Journal of Crystal Growth. 30:357-362 |
| ISSN: | 0022-0248 |
| DOI: | 10.1016/0022-0248(75)90012-3 |
| Popis: | Study of solid state reactions which occur during the synthesis of barium strontium niobate revealed the presence of a previously unrecorded monoclinic phase belonging to the P21/a space group in coexistence with the desired tetragonal phase. Under certain preparation conditions, formation of this phase can produce growth defects in the single crystal. The production of single crystals without defect requires use of raw materials which do not contain this monoclinic phase. Single crystals pulled using the Czochralski method contain striations; these periodic variations of refractive index were shown to be related to a heterogeneous distribution of small quantities of impurities such as calcium and potassium. The growth of single crystals free of striations can be obtained using very pure raw materials by carrying out the pull without rotation and by thermally insulating the upper part of the crucible. These single crystals were tested by the determination of the half wave voltage which was shown to be 85 V, and by the extinction ratio, which is on the order of 30. Experiments of light modulation were also carried out. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|