超冷原子中拓扑超流的发展现状

拓扑超流态是一种奇异物质态，它的内部受能隙保护，而在其系统边缘却可以容纳无能隙的Majorana 费米子。由于该粒子满足非阿贝尔统计，并且受拓扑保护具有良好的稳定性，用它 们携带量子化的信息，可以用于拓扑量子计算的研究。近年来，理论工作预测了各类系统中可能 存在的拓扑超流态。我们首先介绍了在各类光晶格模型中的拓扑超流, 光晶格的超冷原子具有良 好的可控性与普适性，是实现拓扑超流的理想模型系统。接下来我们介绍了自旋轨道耦合调控下 的拓扑超流，自旋轨道耦合效应是诱导拓扑相的重要条件，并且人们已经在实验上合成了人工自 旋轨道耦合，这为实验上观测拓扑超流取得了突破性的进展。随着近年来实验技术的提高，曾经 难以在实验中观测的，被人们所忽略的拓扑Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) 超流相也 成为了人们研究的热点，因此我们接下来介绍了拓扑的FFLO 超流。此外，我们还介绍了拓扑超 流其他方面的进展，包括孤子引诱的拓扑超流、三组分的拓扑超流、大陈数的拓扑超流以及拓扑 超流临界温度的提高。在实验中，如何检测与实现拓扑超流，是其研究的目的及意义所在，因 此我们在文章的最后介绍了拓扑超流的识别与实现。

Development Status of Topological Superfluid in Ultracold Atoms

The topological superfluid state is protected by the energy gap in the bulk, but it can accommodate the gapless Majorana fermions at the edge of the system. The Majorana fermions satisfy non-Abelian statistics and are protected by topology and have good stability, they can carry quantized information and can be used in the study of topological quantum computing. In recent years, theoretical work has predicted the possible topological superfluid states in various systems. Firstly, we introduce the topological superfluid in various optical lattice models. The ultracold atoms of optical lattice have good controllability and universality. It is an ideal model system to realize topological superfluid. Next, we introduce the topological superfluid under the control of spin orbit coupling. The spin orbit coupling effect is an important condition to induce the topological phase, and the artificial spin orbit coupling has been realized in the experiment. Which makes a breakthrough for the experimental observation of topological superfluid. With the improvement of experimental technology in recent years, the topological FFLO superfluid phase, which was difficult to observe in the experiment and ignored by people, has also become a research hotspot. Therefore, we next introduce the topological FFLO superfluid. In addition, we also introduce the progress in other aspects of topological superfluid, including topological superfluid induced by soliton, three-component topological superfluid, topological superfluid with large Chern number, and the high critical temperature of topological superfluid. In the experiment, how to detect and implement topological superfluid is the purpose and significance of our research. Therefore, we introduce the identification and implementation of topological superfluid at the end of the article.