Microstructure and magnetic properties of ordered La_(0.62)Pb_(0.38)MnO_3 nanowire arrays

摘要

Highly ordered La_(0.62)Pb_(0.38)MnO_3 nanowire arrays are successfully fabricated using an improved sol-gel template method. The x-ray diffraction and transmission electron microcopy results reveal that the nanowires are polycrystalline with uniform diameter around 50 nm. Magnetic measurement indicates that the ferromagnetic transition temperature T_c of the nanowires is around 308 K, which is lower than that of the corresponding bulk material. The nanowire arrays demonstrate the perpendicular magnetic anisotropy as a result of shape anisotropy and enhanced coercivity compared with bulk materials and the temperature dependence of the saturation magnetization exhibits a T~(1.25) behaviour. The growth mechanism of the nanowires is also briefly discussed.