Altermagnetism, a new magnetic phase, has been theoretically proposed and
experimentally verified to be distinct from ferromagnetism and
antiferromagnetism. Although altermagnets have been found to possess many
exotic physical properties, the very limited availability of known
altermagnetic materials (e.g., 14 confirmed materials) hinders the study of
such properties. Hence, discovering more types of altermagnetic materials is
crucial for a comprehensive understanding of altermagnetism and thus
facilitating new applications in the next-generation information technologies,
e.g., storage devices and high-sensitivity sensors. Here, we report 25 new
altermagnetic materials that cover metals, semiconductors, and insulators,
discovered by an AI search engine unifying symmetry analysis, graph neural
network pre-training, optimal transport theory, and first-principles electronic
structure calculation. The wide range of electronic structural characteristics
reveals that various novel physical properties manifest in these newly
discovered altermagnetic materials, e.g., anomalous Hall effect, anomalous Kerr
effect, and topological property. Noteworthy, we discovered 8 i-wave
altermagnetic materials for the first time. Overall, the AI search engine
performs much better than human experts and suggests a set of new altermagnetic
materials with unique properties, outlining its potential for accelerated
discovery of the materials with targeting properties.Comment: 38 pages; 22 figures; 3 table