Effect of antiphase boundaries on electrical transport properties of Fe 3O 4 nanostructures

Abstract

Fe 3O 4 nanowires have been fabricated based on Fe 3O 4 thin films grown on α-Al 2O 3 (0001) substrates using the hard mask and ion milling technique. Compared with thin films, the Fe 3O 4 nanowire exhibits a slightly sharper Verwey transition but pronounced anisotropic magnetoresistance properties in the film plane at low magnetic field. Detailed bias-dependence study of both the conductance and magnetoresistance curves for both the thin films and nanowires suggests that the electrical conduction in magnetite near and above the Verwey transition temperature is dominated by a tunneling mechanism across antiphase boundaries. © 2005 American Institute of Physics.