Hits:

Indexed by:期刊论文

Date of Publication:2017-06-01

Journal:NANO RESEARCH

Included Journals:SCIE、EI、Scopus

Volume:10

Issue:6

Page Number:1972-1979

ISSN No.:1998-0124

Key Words:spintronics; Dirac half metal; YN2 monolayer; ferromagnetism

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 x 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.