Herein, a tetragonal Er-doped Pb(MgNb)O–PbTiO single crystal is comprehensively investigated. The actual composition of the studied crystal is Pb(MgNb)O–36PbTiO doped with 0.17-mol% Er (PMN–36PT: 0.17-mol% Er). The crystal exhibits a high shear piezoelectric constant of ∼936 pC/N, approximately three times the longitudinal piezoelectric constant when poled along [001], as well as a higher Curie temperature of ∼170 °C and large coercive field of ∼4.58 kV/cm. At room temperature, the crystal presents a mass of domain walls along the <110> direction and extintion is observed four times within a 360° rotation, showing typical domain features of the tetragonal phase. Under a direct current–electric field along the [010] direction, the extintion rule remains unchanged; however, changes in the domain configuration can be observed. In addition, the orientation dependence of the piezoelectric constant, dielectric coefficient, elastic compliance constant, and electromechanical coupling factor is calculated using the coordinate transformation method. The findings of this study are of considerable importance for the fundamental studies and device design of tetragonal ferroelectric crystals.

中文翻译：

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四方 Er3+ 掺杂 Pb(Mg1/3Nb2/3)O3–PbTiO3 铁电单晶的机电性能和畴演化

在此，对四方掺铒 Pb(MgNb)O-PbTiO 单晶进行了全面研究。研究晶体的实际成分是掺杂 0.17 mol% Er 的 Pb(MgNb)O–36PbTiO（PMN–36PT：0.17 mol% Er）。该晶体表现出约 936 pC/N 的高剪切压电常数，大约是沿 [001] 极化时纵向压电常数的三倍，以及约 170 °C 的较高居里温度和约 4.58 kV/ 的大矫顽场。厘米。在室温下，晶体沿<110>方向呈现大量畴壁，并且在360°旋转内观察到四次消光，显示出四方相的典型畴特征。在沿[010]方向的直流电场下，消光规则保持不变；但是，可以观察到域配置的变化。此外，利用坐标变换方法计算了压电常数、介电系数、弹性柔量常数和机电耦合因子的方向依赖性。该研究结果对于四方铁电晶体的基础研究和器件设计具有重要意义。