Band-gap engineering of La_1-xNd_xAlO₃ (x = 0, 0.25, 0.50, 0.75, 1) perovskite using density functional theory: A modified Becke Johnson potential study

The structural, electronic, and magnetic properties of the Nd-doped Rare earth aluminate, La_1-xNd_xAlO₃ (x = 0% to 100%) alloys are studied using the full potential linearized augmented plane wave (FP-LAPW) method within the density functional theory. The effects of the Nd substitution in LaAlO₃ are studied using the supercell calculations. The computed electronic structure with the modified Becke-Johnson (mBJ) potential based approximation indicates that the La_1-xNd_xAlO₃ alloys may possess half-metallic (HM) behaviors when doped with Nd of a finite density of states at the Fermi level (E_F). The direct and indirect band gaps are studied each as a function of x which is the concentration of Nd-doped LaAlO₃. The calculated magnetic moments in the La_1-xNd_xAlO₃ alloys are found to arise mainly from the Nd-4f state. A probable half-metallic nature is suggested for each of these systems with supportive integral magnetic moments and highly spin-polarized electronic structures in these doped systems at E_F. The observed decrease of the band gap with the increase in the concentration of Nd doping in LaAlO₃ is a suitable technique for harnessing useful spintronic and magnetic devices.