该研究深入探讨了超导体中常见的涡旋自组织现象，并将其与液晶滴中的新发现——阿布里科索夫簇（Abrikosov clusters）——进行了类比。文章首先介绍了超导体的基本特性，即零电阻和迈斯纳效应，并区分了第一类和第二类超导体。特别地，第二类超导体在磁场作用下会形成量子化的涡旋，这些涡旋会形成阿布里科索夫晶格。研究人员发现，在冷却过程中，液晶滴会从各向同性液态转变为手性液态，并观察到类似超导体中的涡旋结构。通过结合实验观测和基于超导体现状的Ginzburg-Landau方程进行理论建模，研究揭示了手性畴（即拓扑缺陷）如何因涡旋排斥和空间限制而聚集。这一发现不仅加深了对涡旋物理学的理解，还可能为操纵和塑造光提供新的途径，在数据通信和天文成像等领域具有潜在应用价值。

✨ 超导体特性与分类：文章首先定义了超导体的核心特征——零电阻和迈斯纳效应，并区分了第一类和第二类超导体。第一类超导体在临界磁场下会突然失去超导性，而第二类超导体则具有两个临界磁场，在两个临界场之间，磁通量会部分进入材料，形成量子化的涡旋。

🌀 涡旋自组织现象：在第二类超导体中，当磁场超过第一临界场时，磁通量会以离散点形式进入，形成量子化的涡旋。这些涡旋相互排斥并自组织成规则的阿布里科索夫晶格。这种现象不仅在超导体中观察到，在玻色-爱因斯坦凝聚和手性磁体中也有类似表现。

🔬 液晶滴中的新发现：本次研究聚焦于液晶滴，观察到在冷却过程中，从各向同性液态转变为手性液态时，出现了与第二类超导体类似的涡旋结构，并将其命名为“阿布里科索夫簇”。研究表明，这些手性畴（拓扑缺陷）的聚集是由于涡旋间的排斥力以及液晶滴的空间限制共同作用的结果。

💡 理论建模与潜在应用：研究人员运用了源自超导性研究的Ginzburg-Landau方程来模拟这一行为，以理解涡旋模式的形成机制。此外，研究还发现穿过手性畴的光会获得手性，这预示着该研究在操纵光方面具有潜力，可能应用于数据通信和天文成像等领域。

Superconductors are materials that, below a certain critical temperature, exhibit zero electrical resistance and completely expel magnetic fields, a phenomenon known as the Meissner effect. They can be categorized into two types.

Type-I superconductors are what we typically think of as conventional superconductors. They entirely repel magnetic fields and abruptly lose their superconducting properties when the magnetic field exceeds a certain threshold, known as the critical field, which depends on both magnetic field strength and temperature.

In contrast, Type-II superconductors have two critical field values. As the magnetic field increases, the material transitions through different states. At low magnetic fields below the first critical field, magnetic flux is completely excluded. Between the first and second critical fields, some magnetic flux enters the material. Above the second critical field, superconductivity is destroyed.

In Type-II superconductors, when magnetic flux enters the material, it does so at discrete points, forming quantized vortices. These vortices repel each other and self-organize into a regular pattern known as the Abrikosov lattice. This effect has also been observed in Bose-Einstein condensates (bosons at extremely low temperatures) and chiral magnets (magnetic materials with spirally aligned magnetic moments). Interestingly, similar vortex self-organization is seen in liquid crystals, offering deeper insights into the underlying physics.

In this study, the researchers investigate vortex behaviour within a liquid crystal droplet, revealing a novel phenomenon termed Abrikosov clusters, which parallels the structures seen in Type-II superconductors. They examine the transition from an isotropic liquid phase to a chiral liquid phase upon cooling. Through a combination of experimental observations and theoretical modelling, the study demonstrates how chiral domains, in other words topological defects, cluster due to the interplay between vortex repulsion and the spatial confinement imposed by the droplet.

To model this behaviour, the researchers use a mathematical framework originally developed for superconductivity called the Ginzburg-Landau equation, which helps identify how certain vortex patterns emerge by minimizing the system’s energy. An interesting observation is that light passing through the chiral domains of the droplet can resultingly obtain chirality. This suggests that the research may offer innovative ways to steer and shape light, making it valuable for both data communication and astronomical imaging.

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Vortex dynamics and mutual friction in superconductors and Fermi superfluids by N B Kopnin (2002)

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