Single-crystalline ferromagnetic Fe1-xCoxSi nanowires

We report the synthesis of ternary Fe1-xCoxSi nanowires by a vapor transport method. Structural characterization of the nanowires shows a single-crystalline nature with B20 crystal structure. Spatially resolved elemental analysis revealed the homogeneous distribution of all elemental components along the nanowire. The nanowire ensemble shows ferromagnetic properties with a sudden change in magnetization at applied magnetic field near zero. Magnetoresistance measurements on a single-nanowire device show positive magnetoresistance, which does not saturate up to the highest applied field. These ferromagnetic nanowires could find application as spin filters in the new field of nanospintronics.