Measurement of piezoelectric constants of lanthanum-gallium tantalate crystal by X-ray diffraction methods

Measurement of independent piezoelectric moduli of Ca3NbGa3Si2O14, La3Ga5.5Ta0.5O14 and La3Ga5SiO14 single crystals

“…In the present work the difference in the measured d 11 was much smaller: 1.53% for LGS, 0.5% for LGT and 0.87% for CNGS crystals. The large difference in the d 11 values obtained by different methods by Blagov et al (2013) is probably due to the inappropriate formula used to calculate the changes in the interplanar distance for tilted planes. Moreover, the method of X-ray quasi-multiple-wave diffraction requires taking into account changes in the angle between tilted planes caused by the electric field.…”

“…It is this effect which is observed under an electric field applied to plates of the X-cut crystals of the 32 symmetry group. Detailed discussion of the results of Blagov et al (2013) can found in Appendix A.…”

Measurement of single-crystal piezo modulus by the method of diffraction of synchrotron radiation at angles near π

“…Estimations of the sensitivity of this method using the example of determination of the piezoelectric constants of a single crystal of lanthanum gallium silicate (LGS, langasite, La 3 Ga 5 SiO 14 ) are shown below. The piezoelectric constants of an LGT crystal have been previously determined by highresolution diffractometry (Blagov et al, 2013). This type of piezoelectric crystal is characterized by several remarkable properties, including the high value of the electromechanical coupling coefficient.…”

Formation of unusual nonferroic domains in TeO2 single crystals under external electric field

“…To date, an electric field is known to manifest itself in X ray diffraction patterns of crystals as a shift in the peak of rocking curves due to the piezo electric effect [1].…”

“…Mutual misorientation and linear sizes of domains formed in ТеО 2 crystal under external electric field (Е = 3750 V/mm): (a) scanning scheme; (b) two dimensional diffraction pattern in the θ)-y coordinates (the angle of incidence of X ray beam and the position of the X ray beam on the sample surface, respectively), which illustrates the spatial localization and change in the rocking curve shape as a result of beam motion over the sample surface (the color indicates the intensity of radiation diffracted by the sample); and (c) examples of triple crystal rocking curves, measured by irradiating with an X ray beam(1,3,5) the sample regions containing individual domains and (2, 4) the regions containing an interdomain boundary.…”