YN2 monolayer： Novel p-state Dirac half metal for high-speed spintronics  

作　　者：Zhifeng Liu Junyan Liu Jijun Zhao 

机构地区：[1]School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China [2]Beijing Computational Science Research Center, Beijing 100094, China [3]Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024, China

出　　处：《Nano Research》2017年第6期1972-1979,共8页纳米研究（英文版）

摘　　要：In spintronics, it is highly desirable to find new materials that can simultaneously possess complete spin-polarization, high-speed conduction electrons, large Curie temperature, and robust ferromagnetic ground states. Using first-principles calculations, we demonstrate that the stable YN2 monolayer with octahedral coordination is a novel p-state Dirac half metal （DHM）, which not only has a fully spin-polarized Dirac state, but also the highest Fermi velocity （3.74×10^5 m/s） of the DHMs reported to date. In addition, its half-metallic gap of 1.53 eV is large enough to prevent the spin-flip transition. Because of the strong nonlocal p orbitals of N atoms （N-p） direct exchange interaction, the Curie temperature reaches over 332 K. Moreover, its ferromagnetic ground state can be well preserved under carrier doping or external strain. Therefore, the YN2 monolayer is a promising DHM for high-speed spintronic devices and would lead to new opportunities in designing other p-state DHMs.In spintronics, it is highly desirable to find new materials that can simultaneously possess complete spin-polarization, high-speed conduction electrons, large Curie temperature, and robust ferromagnetic ground states. Using first-principles calculations, we demonstrate that the stable YN2 monolayer with octahedral coordination is a novel p-state Dirac half metal （DHM）, which not only has a fully spin-polarized Dirac state, but also the highest Fermi velocity （3.74×10^5 m/s） of the DHMs reported to date. In addition, its half-metallic gap of 1.53 eV is large enough to prevent the spin-flip transition. Because of the strong nonlocal p orbitals of N atoms （N-p） direct exchange interaction, the Curie temperature reaches over 332 K. Moreover, its ferromagnetic ground state can be well preserved under carrier doping or external strain. Therefore, the YN2 monolayer is a promising DHM for high-speed spintronic devices and would lead to new opportunities in designing other p-state DHMs.

关 键 词：SPINTRONICS Dirac half metalYN2 monolayer FERROMAGNETISM 

分 类 号：O[理学]