(1. State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China) (2. Beijing Academy of Quantum Information Science, Beijing 100193, China) (3. National Laboratory of Solid State Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China) （4. Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100190, China)
Co-based Heusler alloys have been extensively researched theoretically and experimentally for their high Curie temperature, high spin polarization and good matching to GaAs and MgO substrates, which renders them preferred in spintronic devices. In this review, the structure, magnetic properties and half-metallicity of Co-based Heusler alloys are introduced, and recent progress in exploring and improving the physical properties via substituting atoms, adjusting atomic order or stoichiometric compositions are summarized. Then, brief descriptions about its application in spintronic devices are given, an intense focus is put on magnetic tunneling junction devices with L10-MnAl. Finally, the magnetic and transport features of lately discovered magnetic Weyl semimetal Co2MnGa are presented, and an outlook for its potential application is provided.