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Half‐metallic materials are theoretically predicted to be metallic and insulating, which have not been confirmed experimentally, and the predictions are still in doubt. We report the resistance‐chiral anisotropy (R‐ChA), i.e. chirality‐dependent electrical conductivity, in chiral mesostructured Fe3O4 films (CMFFs) grown on the substrates via a hydrothermal method using amino acids as symmetry‐breaking agents. Two levels of chirality exist in the CMFFs: primary distortion of the crystal lattice forms twisted nanoflakes, and secondary helical stacking of nanoflakes forms fan‐shaped nanoplates. At temperatures below 30 K, the CMFFs exhibited metallic conductivity and insulation for one handedness and the other, respectively. The chirality‐dependent effective magnetic fields were speculated to stabilize the opposite spin in the antipodal chiral frame, which led to the free transport of electrons in one handedness of the chiral structure and immobility for the other handedness. [ABSTRACT FROM AUTHOR]

Half‐metallic materials are theoretically predicted to be metallic and insulating, which have not been confirmed experimentally, and the predictions are still in doubt. We report the resistance‐chiral anisotropy (R‐ChA), i.e. chirality‐dependent electrical conductivity, in chiral mesostructured Fe3O4 films (CMFFs) grown on the substrates via a hydrothermal method using amino acids as symmetry‐breaking agents. Two levels of chirality exist in the CMFFs: primary distortion of the crystal lattice forms twisted nanoflakes, and secondary helical stacking of nanoflakes forms fan‐shaped nanoplates. At temperatures below 30 K, the CMFFs exhibited metallic conductivity and insulation for one handedness and the other, respectively. The chirality‐dependent effective magnetic fields were speculated to stabilize the opposite spin in the antipodal chiral frame, which led to the free transport of electrons in one handedness of the chiral structure and immobility for the other handedness. [ABSTRACT FROM AUTHOR]

The spin-dependent electron transport is theoretically investigated in a two-dimensional electron gas, which is periodically modulated by ferromagnetic and Schottky metal (SM) stripes. We find that the spin-dependent transmission and conductance as well as polarization strongly depend on the number of periods. We also find that the transmission and the polarization of transmitted beams periodically change with increasing the width of the SM stripe. [ABSTRACT FROM AUTHOR]

Abstract: Using the transfer matrix method, the transmission probability, the spin polarization and the conductance of the ballistic electron are studied in detail in a nanostructure with the periodic applied bias and magnetic barriers. We find that these observable quantities sensitively depend on the number of the periodic magnetic–electric barriers. With the number of the periods increasing, the resonance peaks shift towards right and the number of the resonance peaks is increasing as well as the spin polarization being enhanced. These interesting properties may be helpful for making the bias-tunable spin filter. [Copyright &y& Elsevier]