Orientation Dependence of Elastic and Piezoelectric Properties in Rhombohedral BiFeO<sub>3</sub>
oleh: Gang Jian, Fei Xue, Yuhang Guo, Chao Yan
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2018-12-01 |
Deskripsi
Through a coordinate transformation approach, crystal orientation dependences of elastic and piezoelectric properties at room temperature have been investigated in a three-dimensional space for rhombohedral bismuth ferrite (BiFeO<sub>3</sub>). Elastic constants (stiffnesses) <i>c</i><sub>11′</sub>, <i>c</i><sub>12′</sub>, c<sub>13′</sub> and piezoelectric constants <i>d</i><sub>15′</sub>, <i>d</i><sub>31′</sub>, <i>d</i><sub>33′</sub> along arbitrary orientations were obtained based on crystalline asymmetry characteristics of <i>3m</i> point group BiFeO<sub>3</sub>. Parameters along specific orientations obtaining the largest values were presented. The <i>max</i> <i>c</i><sub>11′</sub> = 213 × 10<sup>9</sup> N/m<sup>2</sup> could be achieved in planes with <inline-formula> <math display="inline"> <semantics> <mi>ϕ</mi> </semantics> </math> </inline-formula> = 0° and 90°. The <i>max</i> <i>c</i><sub>12′</sub> = <i>c</i><sub>13′</sub> = 132.2 × 10<sup>9</sup> N/m<sup>2</sup> could be achieved along directions at <i>θ</i> = 13° and <i>θ</i> = 77° inside three mirror planes, respectively. The <i>max</i> <i>d</i><sub>15′</sub> = 27.6 × 10<sup>−</sup><sup>12</sup> C/N and the <i>max</i> <i>d</i><sub>31′</sub> = 12.67 × 10<sup>−</sup><sup>12</sup> C/N could be both obtained along directions at <i>θ</i> = 69° inside mirror planes. The <i>max</i> <i>d</i><sub>33′</sub> = 18 × 10<sup>−</sup><sup>12</sup> C/N could be obtained at <i>θ</i> = 0°, along the spontaneous polarization axis. By adopting optimal directions, the elastic and piezoelectric parameters of BiFeO<sub>3</sub> could be significantly enhanced which shows applications for the growth of BeFeO<sub>3</sub> films with preferred orientations and enhanced properties.