Abstract A deterministic control of vortex chirality in ferroelectrics under a direct electric field is a challenging task. In this study, a novel method is proposed to deterministically switch a single polarization vortex in either a ferroelectric nanowire or a ferroelectric nanodot by using asymmetry electric field. Based on atomic simulations in the framework of the shell model, we demonstrate that the single polarization vortex is easily formed in ferroelectric nanowire or nanodot from a pair of 180°domains, which is generated by asymmetry electric field. More importantly, the use of asymmetry electric field can switch the direction of the 180° domains, and thereby, deterministically switch the chirality of polarization vortex. The present study provides instructive guideline for the future development of nanoscale ferroelectric devices in general and of FRAM in particular.

中文翻译：

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通过直接电场确定性控制铁电纳米结构中的环形力矩

摘要 在直接电场下对铁电体中的涡旋手性进行确定性控制是一项具有挑战性的任务。在这项研究中，提出了一种新方法，通过使用不对称电场确定性地切换铁电纳米线或铁电纳米点中的单极化涡旋。基于壳模型框架中的原子模拟，我们证明了单极化涡流很容易在铁电纳米线或纳米点中从一对 180°域形成，这是由不对称电场产生的。更重要的是，不对称电场的使用可以切换180°域的方向，从而确定性地切换偏振涡旋的手性。