Time-resolved structure analysis of piezoelectric crystals by X-ray diffraction under alternating electric field

Abstract

Rare-earth substitution effects on atomic motions in resonantly vibrating piezoelectric oscillators of langasite-type crystals, namely, La3Ga5SiO14 (LGS) and Nd3Ga5SiO14 (NGS), are revealed by time-resolved X-ray crystal structure analysis under alternating electric fields. Deformations of Ga–O–Ga and Ga–O–Ga/Si bond angles accompanying deformations of RE–O (RE: La or Nd) bond lengths found in LGS are suppressed in NGS. Alternatively, rigid GaO6 octahedra are deformed in NGS. The decreases in RE–O bond lengths and Ga–O–Ga and Ga–O–Ga/Si bond angles caused by the substitution of La by Nd would make the bond lengths and angles more difficult to deform under electric fields; hence, the piezoelectric constants of NGS are smaller than those of LGS.

Transient Crystal Structure of Oscillating Quartz

“…The authors have been investigating the mechanism of piezoelectricity of quartz and other piezoelectric crystals and synthesizing new piezoelectric crystals such as langasite-type crystals to develop crystals with high functional piezoelectricity superior to quartz crystals. In this chapter, we introduce transient crystal structures of quartz and langasite-type crystals oscillating under an alternating electric field measured by synchrotron X-ray diffraction [1][2][3]. Since inverse piezoelectricity is caused by atomic displacements under electric field, measurement of atomic displacements under an electric field is essential to understand the mechanism of piezoelectricity.…”

Scanning time-resolved measurement of transient lattice strain on quartz oscillators resonating under alternating electric field

“…Transient lattice strains during lattice vibration can be measured by time-resolved XRD (TR-XRD). [23][24][25][26][27][28][29][30][31][32] We developed a TR-XRD technique to measure transient lattice strains and atomic displacements in piezoelectric oscillators which were extremely enhanced by their resonant vibrations under an alternating electric field. [27][28][29][30] The TR-XRD technique is applied to the scanning measurement of the transient and local lattice strain on resonating quartz crystals in this study.…”

“…[23][24][25][26][27][28][29][30][31][32] We developed a TR-XRD technique to measure transient lattice strains and atomic displacements in piezoelectric oscillators which were extremely enhanced by their resonant vibrations under an alternating electric field. [27][28][29][30] The TR-XRD technique is applied to the scanning measurement of the transient and local lattice strain on resonating quartz crystals in this study. The effects of the crystal shape and electrode thickness on the transient lattice strain distributions during piezoelectric vibrations are revealed by the method.…”

Time-resolved structure analysis of vibrating gallium phosphate under alternating electric field

“…We have recently succeeded in detecting such small atomic displacements in piezoelectric oscillators of α-quartz (SiO2) and langasitetype crystals (La 3 Ga 5 SiO 14 and Nd 3 Ga 5 SiO 14 ) under alternating electric fields by using a combination of resonant mechanical vibration and time-resolved XRD [1][2][3]. The amplitudes of the mechanical vibration of piezoelectric oscillators under an alternating electric field were resonantly enhanced at the fundamental resonant frequency.…”