Direct comparison of anisotropic magnetoresistance and planar Hall effect in epitaxial Fe3O4 thin films

Anisotropic magnetoresistance across Verwey transition in charge ordered Fe3O4 epitaxial films

“…However, just below T V , the AMR of Fe 3 O 4 (100) film maintains twofold symmetry, revealing that the fourfold APBs are invalid to AMR. Furthermore, Hu et al [21] reported that AMR in the cross-sectional plane of Fe 3 O 4 (100) film shows fourfold symmetry [21], which can rule out the effect of APBs.…”

“…Thus, below T V , AMR in a single-phase monoclinic Fe 3 O 4 should possess twofold symmetry in accordance with the uniaxial magnetocrystalline anisotropy (MCA). However, AMR shows fourfold symmetry in Fe 3 O 4 (100) films below T V [19][20][21]. The contradiction between uniaxial magnetic anisotropy and fourfold AMR must necessarily be clarified.…”

Asymmetric anisotropic magnetoresistance in epitaxial Fe3O4 thin films

“…Details of the growth procedure can be found elsewhere[26]. The epitaxial growth of the Fe 3 O 4 films was confirmed by the sharp RHEED patterns shown in Figs.…”

“…Moreover, the magnetotransport property is still attracting intense studies due to its potential applications in spintronic devices [25] better understanding of the magnetotransport in this material will help better applying it in device applications. Studies on epitaxial Fe 3 O 4 (001) thin films have shown that single-crystalline lattice symmetry induces a fourfold contribution superimposed upon the conventional twofold oscillation of the AMR at temperatures below 200 K [18,26]. Interestingly, the AMR in Fe 3 O 4 (001) thin films at room temperature (RT) exhibits the opposite sign for a current along the high symmetric <100> and <110> directions [18,27], which motivates the study of AMR properties when current flows along axes other than the high symmetry crystal axes.…”

Interfacial Exchange Coupling Induced Anomalous Anisotropic Magnetoresistance in Epitaxial γ′-Fe4N/CoN Bilayers

“…The traditional explanation of AMR and PHE is the change of scattering rate with the angle θ. Hu et al and Li et al observed the different symmetry in AMR and PHE in Fe 3 O 4 and La 2/3 Ca 1/3 MnO 3 films, respectively. 28,29 They found that AMR has a transition from 2-fold to 4-fold symmetry, while PHE only shows a sin2θ dependence. They explain the distinction according to the original resistivity tensor formula.…”