Electrical detection of magnetic domain wall in Fe₄N nanostrip by negative anisotropic magnetoresistance effect Available to Purchase

The magnetic structure of the domain wall (DW) of a 30-nm-thick Fe₄N epitaxial film with a negative spin polarization of the electrical conductivity is observed by magnetic force microscopy and is well explained by micromagnetic simulation. The Fe₄N film is grown by molecular beam epitaxy on a SrTiO₃(001) substrate and processed into arc-shaped ferromagnetic nanostrips 0.3 μm wide by electron beam lithography and reactive ion etching with Cl₂ and BCl₃ plasma. Two electrodes mounted approximately 12 μm apart on the nanostrip register an electrical resistance at 8 K. By changing the direction of an external magnetic field (0.2 T), the presence or absence of a DW positioned in the nanostrip between the two electrodes can be controlled. The resistance is increased by approximately 0.5 Ω when the DW is located between the electrodes, which signifies the negative anisotropic magnetoresistance effect of Fe₄N. The electrical detection of the resistance change is an important step toward the electrical detection of current-induced DW motion in Fe₄N.