Distinctive uniaxial magnetic anisotropy and positive magnetoresistance in (110)-oriented Fe{sub 3}O{sub 4} films

Magnetite (Fe{sub 3}O{sub 4}) films were synthesized on (110)-oriented MgO, MgAl{sub 2}O{sub 4}, and SrTiO{sub 3} substrates for comparative studies of the substrates' effects on magnetic and magnetoresistance properties of the films. For the [-110] direction, the hysteresis loops of the Fe{sub 3}O{sub 4} film on MgAl{sub 2}O{sub 4} exhibited a good squareness with the largest coercivity of ∼1090 Oe, and the ratio of remanent magnetization to saturation magnetization was ∼0.995. For the [001] direction, positive magnetoresistance in weak magnetic fields was most distinct for the (110) SrTiO{sub 3} substrate with the largest lattice mismatch. Positive magnetoresistance in the (110) Fe{sub 3}O{sub 4} films was presumably affected by imperfect atomic arrangements at anti-phase boundaries.