Fig. 6: An oxygen vacancy complex in a MgO MTJ whose DOS intersects the Fermi level: a possible candidate.
From: Oxygen vacancy-driven spin-transfer torque across MgO magnetic tunnel junctions
a Schematic of the zig-zag chain of oxygen vacancies in 5 ML f.c.c. MgO(001) spanning the bcc Fe(001) electrodes. Density of states calculated for a Fe(MLs 1-4)/MgO(5 ML)/Fe(MLs 5-7) MTJ, with (b) intrinsic/defect-free MgO, and (c) a zig-zag chain of oxygen vacancies that spans the MgO layer (a). In (c), the P (black) and AP (red) cases are distinguished. In the ideal MTJ, MIGS promote DOS at EF on the first two MgO MLs away from Fe, but not on the central MgO layer. This prerequisite toward metallic conduction is fulfilled by the zig-zag chain of oxygen vacancies complex, as a possible candidate.
