JACS: the second army of Nanjing University of science and technology, the research group of Professor Deng Kaiming and Fudan University jointly published papers to the professor of the Red Army

Recently, Professor Yi Erjun, Nanjing University of science and technology, Professor Deng Kaiming and Fudan University cooperated with professors of the Red Army to publish a research paper entitled "ultra high temperature ferromagnetism in internal tetrahedral semiconductors" (DOI: 10.1021 / JACS 9b06452) on the international top journal of the American Chemical Society Huang Chengxi is the first author of the paper Journal of the American Chemical Society, published by the American Chemical Society, is the top journal in physical chemistry, material chemistry and related fields Ferromagnetic Semiconductors integrate the advantages of traditional ferromagnetic materials and semiconductor materials, so it is of great significance for the construction of future spin electronic devices with low energy consumption, high performance and multi-function, such as tunneling magnetoresistance sensors, spin field effect transistors, magnetic capacitors, magnetic random access memories and quantum computing / communication devices The research on Ferromagnetic Semiconductors has lasted for half a century, but the Ferromagnetic Semiconductors which can work at room temperature have not been found by experiments In addition, how to be compatible with the ferromagnetic semiconductor materials and the traditional semiconductor materials used in the semiconductor industry has become an urgent practical problem Professor Yi Erjun's team has been devoted to revealing the physical nature of magnetism and searching for practical high-temperature ferromagnetic materials for many years, and has obtained many research results in the field of ferromagnetic electric semiconductors (Phys Rev Lett, 2018, 120, 147601; nano letters, 2015, 15, 8277; nano letters, 2016, 16, 8015; J am Chem SOC, 2012, 134, 5718) In recent research work (J am Chem SOC 2018, 140, 11519), the team proposed to improve Curie temperature of ferromagnetic semiconductor to above room temperature by constructing binary alloy compound In this latest research work, the team once again put forward a pioneering idea to realize high temperature ferromagnetic semiconductor The traditional ferromagnetic semiconductor materials are octahedral crystal structure, that is, the magnetic transition metal atoms are located in the center of the octahedron composed of six coordination non-metal atoms In fact, such crystal structure usually leads to strong antiferromagnetic direct exchange between transition metal ions, which is not conducive to the realization of strong ferromagnetic coupling For another kind of crystal structure, tetrahedral crystal structure, such as zinc oxide with zinc blende configuration, transition metal atom is located in the center of tetrahedron composed of four coordination non-metal atoms With the help of tight binding model analysis, they found that the special orbital symmetry of this kind of crystal structure makes its inherent direct exchange of antiferromagnetism very weak compared with octahedral crystal Therefore, the ferromagnetic coupling of tetrahedral Ferromagnetic Semiconductors may be stronger than that of octahedral Ferromagnetic Semiconductors According to this new idea, they theoretically predicted a series of tetrahedral intrinsic Ferromagnetic Semiconductors, in which the CRC Ferromagnetic Semiconductors with zinc blende configuration have Curie temperatures of more than 1000 K More interestingly, these materials have very similar crystal structure with traditional semiconductors such as Gan and ZnO, so they can be synthesized directly on the surface of these semiconductors by molecular beam epitaxy growth method to form ferromagnetic semiconductor / ordinary semiconductor heterostructure, which can be well compatible with the widely used semiconductor devices such as CMOS devices Their discovery will greatly promote the theoretical and applied research of room temperature ferromagnetic semiconductors This work has been supported by the National Natural Science Fund, Jiangsu Natural Science Fund and the special funds for basic scientific research business expenses of central universities.