Study of the piezoelectric properties of Ba2Ge2TiO8 glass-ceramic and single crystals

Oriented Nucleation of both Ge-Fresnoite and Benitoite/BaGe4O9 during the Surface Crystallisation of Glass Studied by Electron Backscatter Diffraction

“…XRD-patterns of the surface crystallized layers showed a non-statistical orientation distribution indicating a 001 texture7913141617181920212224 which increased in intensity after 5 μm or more of the surface were removed9192124. Including a nucleation step into the annealing regime was reported to reduce the degree of orientation9.…”

“…Apart from growing single crystals in the Czochralski process, glass-ceramic materials containing oriented BTG crystals have been produced via the surface crystallization of glasses789101112131415161718192021222324. Highly oriented glass-ceramics containing e.g.…”

“…In order to suppress bulk nucleation7 and to increase the degree of crystal orientation7, the surface crystallization experiments have been modified using a temperature gradient789101112 or an ultrasonic treatment of the surface13. However, other experiments showed that oriented crystallization at the surface also occurs without these experimental efforts1415161718192021222324.…”

“…Including a nucleation step into the annealing regime was reported to reduce the degree of orientation9. Samples annealed at only 695 and 700 °C have been proposed to show XRD-patterns similar to the powder pattern16 and it was concluded that the crystalline phase is not oriented at the surface161724.…”

Pockels effect of silicate glass-ceramics: Observation of optical modulation in Mach–Zehnder system

“…For example, second-order optical nonlinearity for the Ba 2 TiSi 2 O 8 -, Sr 2 TiSi 2 O 8 - and Ba 2 TiGe 2 O 8 -surface-crystallized GCs, which is measured by means of second-harmonic generation (SHG), has been reported to be d 33  ~ 13 pm/V, d 33  ~ 7.2 pm/V and d 33  ~ 22 pm/V, respectively, and is closely related to the ratio of lattice constant of a-axis to that of lattice constant of c -axis, i.e., a / c (or tetragonality)12. Fresnoite-crystallized GCs have been intensively studied from viewpoint of both fundamental glass-science and practical application so far1314151617181920212223. In this study, we focused on 35SrO–20TiO 2 –45SiO 2 (STS45) glass, which singly crystallizes fresnoite-type Sr 2 TiSi 2 O 8 .…”