On Feb. 28, 2019, research groups from the Institute of Physics of the Chinese Academy of Sciences, Nanjing University and Princeton University published their findings on topological materials in Nature. 

Their studies showed that thousands of known materials may have topological properties, i.e., about 24% of materials in nature may have topological structures. Topology is the study of geometric properties and spatial relations that are unaffected by the continuous change of shape or size of figures. 

The introduction of topology, a mathematical concept, into the field of physics not only promotes the development of basic physics research but also stimulates the discovery of a large amount of materials having novel properties.