滑动铁电性的多极方法

中文摘要 AI 辅助

铁电性的传统理论处理并不能直接推广到滑动铁电体，滑动铁电体是日益受到研究的层状材料，其中可切换的电极化由堆叠层的二维相对运动控制。因此，对决定其极化行为的潜在过程进行深入分析仍然具有挑战性。在本文中，我们提出了一种全面的方法，用于识别驱动这种极化出现的对称性适配的微观参数。首先，我们概述了我们的方法，该方法借助群论论证和Wannier轨道密度的畸变，将宏观对称性与决定铁电性出现的微观电子畸变联系起来。然后，我们通过使用密度泛函理论将我们的策略应用于蜂窝状双层系统（包括六方氮化硼）来说明这一过程。通过这种方式，我们发现孤对电子轨道的偶极型和四极型畸变的组合控制了电子重组，进而控制了此类系统中的铁电性。

英文摘要

Traditional theoretical treatments of ferroelectricity do not straightforwardly extend to sliding ferroelectrics, which are increasingly-studied layered materials where a switchable electrical polarization is controlled by two-dimensional relative motion of the stacked layers. Therefore, in-depth analyses of the underlying processes which dictate their polarization behavior remain challenging. In this paper, we present a comprehensive approach for identifying the symmetry-adapted microscopic parameters which are responsible for driving the emergence of this polarization. First, we outline our approach, which appeals to group theory arguments and the distortion of Wannier orbital densities to connect macroscopic symmetries to the microscopic electronic distortions which dictate the appearance of ferroelectricity. Then, we illustrate this process by using density functional theory to apply our strategy to honeycomb bilayer systems, including hexagonal boron nitride. In this way, we find that combinations of dipole-like and quadrupole-like distortions of lone pair electron orbitals control electronic reorganization, and by extension, ferroelectricity in such systems.

发表机构

• Cornell University（康奈尔大学）

机构由 AI 辅助整理，请以论文原文为准。