"YN<sub>2</sub> monolayer: Novel p-state Dirac half metal for high-spee" by Zhifeng Liu, Junyan Liu et al.

Article Title

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

Authors

Zhifeng Liu, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China Beijing Computational Science Research Center, Beijing 100094, China
Junyan Liu, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China
Jijun Zhao, Beijing Computational Science Research Center, Beijing 100094, China Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024, China

Keywords

spintronics, Dirac half metal, YN2 monolayer, ferromagnetism

Abstract

ABSTRACT 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 × 105 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.