近日，华南理工大学的Satoshi Aya&黄明俊及其研究团队取得一项新进展。经过不懈努力，他们发现了液体-物质螺旋电学中挠曲电驱动的环形极拓扑结构。相关研究成果于2024年3月18日在国际知名学术期刊《自然—物理学》上发表。

该研究团队发现了一种具有极化螺旋的涌现铁电液态中的自发环面极性拓扑，称为“螺旋向列”。液晶弹性和极性相互作用之间的互动导致偏振的连续平面内旋转，产生周期性的环面装配。

与磁性部分相似，邻近的环面畴被圆形畴壁隔开。局部极化切换使环形畴具有独特的收缩和膨胀动力学特性。这一发现为开发可设计和可切换的铁电-液物质光电子学提供了机会。

据悉，磁偶极子和电偶极子具有相似的对称性，因此预计会表现出许多共同的结构。然而，尽管经常报道由磁偶极子组成的各种自旋织构，但直到最近，对长程有序电偶极子的研究还很少。

附：英文原文

Title: Flexoelectricity-driven toroidal polar topology in liquid-matter helielectrics

Author: Yang, Jidan, Zou, Yu, Li, Jinxing, Huang, Mingjun, Aya, Satoshi

Issue&Volume: 2024-03-18

Abstract: Magnetic and electric dipoles have similar symmetry and are therefore expected to exhibit many common structures. However, despite frequent reports of various spin textures composed of magnetic dipoles, investigations on long-range ordered electric dipoles have been scarce, until recently. Here we discover spontaneous toroidal polar topology in an emerging ferroelectric liquid state with polarization helices, dubbed ‘helielectric nematic’. The interplay between liquid-crystal elasticity and polar interactions results in a continuous in-plane rotation of the polarization, producing a periodic toroidal assembly. In partial analogy with magnetism, the neighbouring toroidal domains are separated by circularly shaped domain walls. The local polarization switching enables unique shrinkage and expansion dynamics of the toroidal domains. The discovery provides opportunities for developing designable and switchable ferroelectric-liquid-matter opto-electronics.

DOI: 10.1038/s41567-024-02439-7

Source: https://www.nature.com/articles/s41567-024-02439-7