Realization of a half-metallic state on bilayer WSe2 using doping transition metals (Cr, Mn, Fe, Co, Ni) in its interlayer

摘要

The structural, electronic and magnetic properties of Cr, Mn, Fe, Co and Ni-doped bilayer WSe2 are predicted by using first principles calculations. The doped transition-metal (TM) atoms show a covalent-binding with the nearest Se atoms. The calculated electronic structures reveal that the TM Cr, Mn, Fe and Co-doped bilayer WSe2 exhibits a half-metallic character with a 100% spin polarization at the Fermi level, and the reason is ascribed to the strong hybridization peak between the transition metals and the parent W and Se atoms. The Ni-doped bilayer WSe2 is still a semiconductor with nonmagnetism. The Fe-doped system has a robust stability of half-metallicity because there are three connected states peak spanning the Fermi level. The doping of Cr, Mn, Fe and Co atoms leads to a prominent total magnetism (0.93-3.65 mu(B) moment per unit cell), and an induced similar to 0.3 mu(B) moment in parent W atoms is found in addition to the main contribution of TM atomic magnetism (0.71-3.33 mu(B) moment per atom). The predicted Cr, Mn, Fe and Co-doped bilayer WSe2 should be the candidate materials for spintronic devices due to their magnetic and half-metallic nature.