Anisotropic domain switching paths in [001]‐, [011]‐, and [111]‐poled Pb(Mg_1/3Nb_2/3)O₃‐0.30PbTiO₃ single crystals were studied by in situ polarized light microscopic driven by an antiparallel electric field. Orientation‐dependent electric field induced polarization and strain behaviors were investigated systematically. For [001]‐oriented crystals, only one‐step 71° switching occurred during the domain switching process, resulting in the appearance of stripe domain walls whose traces on (001) plane were along 45° or 135° with respect to [100] direction. But for [011]‐oriented samples, a two‐step 71° switching was observed during 109° switching and the projections of formed twin domain walls on the (011) plane are along 35.3° or 144.7° with respect to [01] direction. Moreover, a three‐step 71° switching was found during 180° switching in [111]‐oriented samples. It was demonstrated by the produced domain walls whose projections on the (10) plane are along 35.3°, 90° or 160.6° with respect to [11] direction. The energetically motivated mechanism based on multistep polarization switching process was also proposed to explain the anisotropic domain switching paths. Our results provided a visualized observation on the ferroelectric domain switching process and also laid the solid foundations for controlling polarization order parameter in ferroelectric single crystals.

中文翻译：

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具有菱面体结构的Pb（Mg1 / 3Nb2 / 3）O3-0.30PbTiO3单晶的各向异性畴切换

[001]-，[011]-和[111]-极化Pb（Mg _1/3 Nb _2/3）O ₃ -0.30PbTiO _3中的各向异性域切换路径通过反平行电场驱动的原位偏振光显微镜研究了单晶。系统研究了与方向有关的电场引起的极化和应变行为。对于[001]取向的晶体，在畴切换过程中仅发生一步71°切换，导致出现条纹状畴壁，其在（001）平面上的迹线相对于[100]沿45°或135°方向。但是对于[011]取向的样品，在109°转换过程中观察到两步71°转换，并且在（011）平面上形成的双畴壁的投影相对于[01]沿35.3°或144.7°] 方向。此外，在[111]方向的样本中，在180°切换期间发现了三步71°切换。通过生产的畴壁证明了这一点，该畴壁在（1 0）平面上的投影相对于[11 ]方向沿35.3°，90°或160.6° 。还提出了基于多步极化切换过程的能量激励机制来解释各向异性域切换路径。我们的结果提供了对铁电畴切换过程的可视化观察，也为控制铁电单晶的极化有序参数奠定了坚实的基础。