A stable 4f half-metallic ferromagnetism Eu4O3N predicted from GGA+U calculations

Abstract

Objective: Half-metallic ferromagnetism plays a major role in high-performance spintronic applications due to its 100% spin-polarization. So, it is very necessary to search better half-metallic ferromagnets with large magnetic moment and being compatible with current semiconductor technology.Methods: We study cubic Eu4O3N on the basis of state-of-the-art first-principles calculations by using generalized gradient approximation plus U method.Results: It is found that the Eu4O3N is a half-metallic ferromagnet with a half-metallic gap of 376meV and the large Eu ion magnetic moment up to about 7μB. The structural and ferromagnetic stability are proved by mechanical stability criterion and magnetic energy differences, respectively. The half-metallic properties are also stable against the isotropic strain, volume-conservative tetragonal strain and rhombohedral distortion. For the choice of U between 4 and 8eV, the Eu4O3N still is half-metallic ferromagnet.Conclusion: This provides a new idea for searching new half-metallic ferromagnetism by f electrons.Practical implications: If the Eu4O3N was experimentally synthesized with half-metallic properties, it should be used to design high-performance spintronic devices.