Applications of Thin-film Topological Insulators in Ultrafast Optical Devices

With the development of ultrafast optics and the in- depth research on topological insulator materials represented by Bi2Te3, the research on applying topological insulator thin films to ultrafast lasers and devices has developed rapidly, and a series of research results have been published in recent years. This paper reviews the research on ultrafast lasers and devices based on topological insulator materials by starting from structure characteristics and preparation methods, introducing their unique optical and optoelectronic properties,summarizing the research on their applications in ultrafast lasers and optical devices, as well as reviewing and discussing the achievements and challenges in this field. We also provide an outlook on further development directions on the application of topological insulator thin film materials in ultrafast optics.