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• Nonlinear model for a bended piezoelectric semiconductor beam is established. • Differential quadrature method based iteration procedure is developed. • Nonlinearity of constitutive relation and non-uniformity of structure are focused. • Potential barriers and wells are realized through designing structures. In this paper, the effects of nonlinear constitutive relation on the electro-elastic coupling behaviors in non-uniform piezoelectric semiconductor beams are investigated. On the basis of three-dimensional theory for piezoelectric semiconductor and double power series, one-dimensional bending model is developed. In order to deal with the nonlinear problem, a differential quadrature method based iteration procedure is proposed. Comparing with the results from finite element method, the proposed method has good convergence and high accuracy. In numerical analysis, the effects of nonlinearity and non-uniformity in piezoelectric semiconductor are discussed thoroughly. It is found the introduction of nonlinearity induces the loss of symmetric for all electrical field quantities but little changes the mechanical quantities. While the reduction of width along the length direction produces larger mechanical and electrical responses. Importantly, the effects of nonlinearity on the electrical field quantities are more evident in a piezoelectric semiconductor beam with rapidly varied cross section. Besides, we designed the piezoelectric semiconductor beams subject to double shear forces and a beam with locally varied cross section. In the designed structures, the potential barriers and wells are realized, which provide new approaches adjusting the electro-elastic behaviors in piezoelectric semiconductors. The study in this paper could be the guidance designing high performance electronic devices. [ABSTRACT FROM AUTHOR]

The fundamental shear horizontal (SH0) waves have been proved to be a very useful method for non-destructive testing due to their non-dispersive characteristics. Currently, although several methods have been proposed to generate SH0 waves, it is still a challenge to obtain pure SH0 wave mode efficiently. Herein, in this study, non-centrosymmetric YBa3(PO4)3 (YBP) and YbBa3(PO4)3 (YbBP) crystals with pure face-shear mode were grown via the traditional Czochralski pulling method at temperatures above 1800 °C. High resolution X-ray diffraction was carried out to evaluate the crystalline quality. Results showed that the YBP and YbBP crystals were of good quality, with the full width at half-maxima being on the order of 42.5″ and 52.3″, respectively. Moreover, the full set of electro-elastic constants for the YBP and YbBP crystals were determined and collated using a combination of impedance and pulse-echo methods. The piezoelectric coefficient (d14) of the YBP and YbBP crystals were determined to be 10.6 pC/N and 11.4 pC/N, respectively, corresponding to the electromechanical coupling coefficient (k14) equal to 15.4% and 15.9%, exhibiting large and pure face-shear vibration mode. Collectively, these results indicate that the YBP and YbBP crystals are promising for acoustic wave sensing application.

Lithium niobate crystals (LiNbO3, LN) are multifunctional crystal materials with many outstanding properties. In this work, the electro-elastic properties of LN single crystals were explored at temperatures from −150 °C to 150 °C. The temperature dependences of dielectric permittivities, elastic compliances, electromechanical coupling factors and piezoelectric coefficients were determined using the impedance method. The LN crystals possessed large dielectric permittivities, the ε 11 T / ε 0 and ε 33 T / ε 0 were 83.2 and 29.4 at room temperature, respectively. The elastic compliances s11, s13, s33 and s44 presented a positive increase as the temperature increased, and the variations were 5.0%, 8.2%, 4.6% and 5.4%, respectively, showing a good temperature stability. Moreover, the temperature dependence of the electromechanical coupling factors and piezoelectric coefficients for different vibration modes were studied with a temperature range from −150 °C to 150 °C, where the thickness shear vibration mode d15 presented a large piezoelectric response and minimal temperature variation. [ABSTRACT FROM AUTHOR]

Lithium niobate crystals (LiNbO3, LN) are multifunctional crystal materials with many outstanding properties. In this work, the electro-elastic properties of LN single crystals were explored at temperatures from −150 °C to 150 °C. The temperature dependences of dielectric permittivities, elastic compliances, electromechanical coupling factors and piezoelectric coefficients were determined using the impedance method. The LN crystals possessed large dielectric permittivities, the ε11T/ε0 and ε33T/ε0 were 83.2 and 29.4 at room temperature, respectively. The elastic compliances s11, s13, s33 and s44 presented a positive increase as the temperature increased, and the variations were 5.0%, 8.2%, 4.6% and 5.4%, respectively, showing a good temperature stability. Moreover, the temperature dependence of the electromechanical coupling factors and piezoelectric coefficients for different vibration modes were studied with a temperature range from −150 °C to 150 °C, where the thickness shear vibration mode d15 presented a large piezoelectric response and minimal temperature variation.

The non-centrosymmetric bismuth-based oxyborate crystals have been extensively studied for non-linear optical, opto-electric and piezoelectric applications. In this work, single crystal growth and electro-elastic properties of α-BiB3O6 (α-BIBO) and Bi2ZnB2O7 (BZBO) crystals are reported. Centimeter-sized α-BIBO and BZBO crystals were grown by using the Kyropoulos method. High resolution X-ray diffraction tests were performed to assess the crystal quality. The full-width at half-maximum values (FWHM) of the rocking curves were evaluated to be 35.35 arcsec and 47.85 arcsec for α-BIBO and BZBO samples, respectively. Moreover, the electro-elastic properties of α-BIBO and BZBO crystals are discussed and summarized, based on which the radial extensional and the face shear vibration modes were studied for potential acoustic device applications. The radial extensional mode electro-mechanical coupling factors kp were evaluated and found to be 32.0% and 5.5% for α-BIBO and BZBO crystals, respectively. The optimal crystal cuts with face shear mode were designed and found to be (YZt)/−53° (or (YZt)/37° cut) for α-BIBO crystal, and (ZXt)/±45° cut for BZBO crystal, with the largest effective piezoelectric coefficients being in the order of 14.8 pC/N and 8.9 pC/N, respectively.

A series of K(H1− xD x)2PO4 crystals were grown from deuterated aqueous solution by using a point-seed rapid-growth method. The elastic, piezoelectric and dielectric constants of these crystals were determined using the resonance technique and impedance analysis, respectively. The elastic compliance constant s11 measured in this experiment is larger than that in previous experiments, and the reliability of the results presented herein has been verified. These results show that, with increasing content of deuterium, s11, s44, s66, d36, e36 and k36 are gradually increased, whereas s12, s13, s33, d14, e14 and k14 have no demonstrable variation. The reasons for the composition dependence of these constants were analyzed based on the variation of the crystal structures resolved by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The non-centrosymmetric bismuth-based oxyborate crystals have been extensively studied for non-linear optical, opto-electric and piezoelectric applications. In this work, single crystal growth and electro-elastic properties of α-BiB3O6 (α-BIBO) and Bi2ZnB2O7 (BZBO) crystals are reported. Centimeter-sized α-BIBO and BZBO crystals were grown by using the Kyropoulos method. High resolution X-ray diffraction tests were performed to assess the crystal quality. The full-width at half-maximum values (FWHM) of the rocking curves were evaluated to be 35.35 arcsec and 47.85 arcsec for α-BIBO and BZBO samples, respectively. Moreover, the electro-elastic properties of α-BIBO and BZBO crystals are discussed and summarized, based on which the radial extensional and the face shear vibration modes were studied for potential acoustic device applications. The radial extensional mode electro-mechanical coupling factors kp were evaluated and found to be 32.0% and 5.5% for α-BIBO and BZBO crystals, respectively. The optimal crystal cuts with face shear mode were designed and found to be (YZt)/−53° (or (YZt)/37° cut) for α-BIBO crystal, and (ZXt)/±45° cut for BZBO crystal, with the largest effective piezoelectric coefficients being in the order of 14.8 pC/N and 8.9 pC/N, respectively. [ABSTRACT FROM AUTHOR]