A probable half-metallic nature is suggested for these systems with supportive integral magnetic moments and high spin polarized electronic structures in these doped cases at E F. The calculated magnetic moments in La 1 À x Nd x AlO 3 were found to arise mainly from the Nd-4f state electrons. The direct and indirect band gaps were studied as a function of Nd concentration in LaAlO 3.
The La 1 À x Nd x AlO 3 may possess half metallic behavior on Nd doping with finite density of states at E F. The electronic structures were computed using modified Beck Johnson (mBJ) potential based approximation with the inclusion of Coulomb energy (U) for Nd-4f state electrons. The effects of Nd substitution in LaAlO 3 are studied using super-cell calculations. The structural, electronic and magnetic properties of Nd-doped Rare earth aluminate, La 1 À x Nd x AlO 3 (x ❀–100%) are studied using the full potential linearized augmented plane-wave (FP-LAPW) method within the density functional theory. Ferromagnetic state of nanostructured BiFe 2 O 4.5 is in contrast with its bulk counterparts. Temperature dependent magnetization studies implied anti-ferromagnetic interactions for BiMn 2 O 5, frustrated magnet for BiFeMnO 5 and ferromagnetic behaviour for BiFe 2 O 4.5. Isothermal magnetization plots (at 5 K) show increase in coercivity (H c) from x = 0 to x = 2. These values appear to be larger than that reported for bulk. From optical studies, it has been found that the observed energy band gap values are strongly related to 3d electron numbers. Transmission electron microscopic images confirm that the average particle size of all the materials are in nano domain range with different morphologies. The observed structural changes via tuning of B-site (x = 0–2) played an important role in overall magnetic properties.
Noticeable expansion in unit cell parameters has been found from BiMn 2 O 5 (x = 0) to BiFe 2 O 4.5 (x = 2). X-ray diffraction data (XRD) revealed orthorhombic phase with Pbam space group.
Nanostructures of complex oxides have been designed to study their structural, optical and magnetic behaviour.
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