Tunable electronic and magnetic properties of antimonene system via Fe doping and defect complex: A first-principles perspective

摘要

We investigate the electronic and magnetic properties of Fe-doped (Fe-sb) and defect complex (Fe-sb + V-sb) tuned antimonene systems. Our calculations showed that the method of generalized gradient approximation with on-site Coulomb repulsion (GGA+U) obtained a larger magnetic moment in the two defect systems than that of generalized gradient approximation (GGA). When the spin-orbit couplings (SOC) effects were turned on, the Fe-doped system transforms from a narrow band-gap semiconductor to a semimetallic material by the scheme of GGA+U. Moreover, the concurrence of strong orbital hybridization (p-d) and spin-orbit interaction lead to a significant spin splitting around the Fermi level. Especially, stable room temperature ferromagnetism (RTFM) is obtained in Fe-doped systems. However, the system presents anti-ferromagnetism (AFM) order when two intrinsic vacancies (V-sb) are introduced into the Fe-doped systems, which is not conducive to Fe-doped antimonene materials applied in spintronics devices. Comparing with pure antimonene, the relatively flat impurity band indicates lower carrier mobility in Fe-sb + V-sb system. Hence, in Fe-doped antimonene materials, the intrinsic vacancies should be effectively suppressed in experimental fabrication. (C) 2018 Elsevier B.V. All rights reserved.