Magnetism, half-metallicity, and topological signatures in Fe2-xVxPO5 (x = 0, 0.5, 1, 1.5, 2) materials: a potential class of advanced spintronic materials

Abstract

Novel spintronic materials combining both magnetism and nontrivial topological electronic structures have attracted increasing attention recently. Here, we systematically studied the doping effects, magnetism, half-metallicity, and topological properties in the family of Fe_2-xV_xPO₅ (x = 0, 0.5, 1, 1.5, 2) compounds. Our results show that Fe₂PO₅ takes an antiferromagnetic (AFM) ordering with a zero total magnetic moment. Meanwhile, the material hosts a Dirac nodal line and a Weyl nodal line near the Fermi level. V₂PO₅ is a ferromagnetic (FM) nodal line half-metal with a 100% spin-polarized Weyl nodal line. After doping, we find that Fe_1.5V_0.5PO₅, Fe₁V₁PO₅ and Fe_0.5V_1.5PO₅ all take ferrimagnetic (FiM) ordering, with the Fe and V atoms taking opposite spin directions. Both Fe_1.5V_0.5PO₅ and Fe_0.5V_1.5PO₅ are FiM half-metals. Meanwhile, they show several pairs of fully spin-polarized Weyl points near the Fermi level. Fe₁V₁PO₅ is a FiM semiconductor with different sizes of band gaps in different spin channels. These Fe_2-xV_xPO₅ materials not only provide a good research platform to study the novel properties combining magnetism and nontrivial band topology, but also have promising applications in spintronic applications.