近日，美国美国科罗拉多大学博尔德分校Ivan I. Smalyukh团队研究了类粒子手性向列涡旋结的聚变和裂变。这一研究成果发表在2025年12月15日出版的《自然—物理学》杂志上。

涡旋结在许多物理系统中已被发现在衰减。

研究组描述了拓扑保护涡旋结，它保持稳定，经历离子和裂变，并保持拓扑不变性。宿主介质是一种手性向列液晶，表现出分子排列的固有手性，而涡旋线的核心在结构上是非手性区域，其中分子扭曲无法定义。研究组可以通过施加电脉冲在这些漩涡结的离子和裂变之间可逆地切换。这揭示了结理论中概念的物理体现，如结的连接和带手术。

该发现证明了手性效应在从组成分子到宿主介质的层次上的相互作用，以及能量稳定的手性涡旋结。这种新兴的物理行为可能使其在电光和光子学中的应用成为可能，其中涡旋结的这种聚变和裂变过程可用于控制光。

附：英文原文

Title: Fusion and fission of particle-like chiral nematic vortex knots

Author: Hall, Darian, Tai, Jung-Shen Benny, Kauffman, Louis H., Smalyukh, Ivan I.

Issue&Volume: 2025-12-15

Abstract: Vortex knots have been seen decaying in many physical systems. Here we describe topologically protected vortex knots, which remain stable and undergo fusion and fission and conserve a topological invariant. The host medium, a chiral nematic liquid crystal, exhibits intrinsic chirality of molecular alignment, whereas cores of the vortex lines are structurally achiral regions in which a molecular twist cannot be defined. We can reversibly switch between fusion and fission of these vortex knots by applying electric pulses. This reveals the physical embodiments of concepts in knot theory, such as connected sums of knots and band surgeries. Our findings demonstrate the interplay of chirality effects at hierarchical levels from constituent molecules to the host medium and the energetically stable chiral vortex knots. This emergent physical behaviour may enable applications in electro-optics and photonics in which such fusion and fission processes of vortex knots can be used for controlling light.

DOI: 10.1038/s41567-025-03107-0

Source: https://www.nature.com/articles/s41567-025-03107-0