arXiv subjects

A. Lakdja

Publications and source records attributed to A. Lakdja.

2 recordsLinked to original sources

arXiv2025

Phase stability and structural properties of the K$_{x}$Ca$_{1-x}$N novel ferromagnetic alloy from first-principles

We study the structural properties and phase stability of the K$_{x}$Ca$_{1-x}$N alloy using the regular-solution model based on the total energy of the mixing. The pseudopotential approach was used along with PBE functional of Perdew, Burke, and Ernzerhof (PBE). We investigated the bond-lengths distribution as a function of composition $x$. We also predicted the phase separation of the two partially miscible components and calculated the enthalpy $ΔH$ using the interaction parameter $Ω$. We observe an asymmetry about $x=0.46$ in the phase diagram due to the $x$-dependant interaction parameter $Ω=12.69-1.32x$ kcal/mole. The equilibrium solubility limit, known as the miscibility gap is found to be around 3033 K.

cond-mat.mtrl-sci↗

arXiv2020

Magnetism in Rb$_{x}$Sr$_{1-x}$C novel alloy

We report a study on the electronic and magnetic properties of a novel Rb$_{x}$Sr$_{1-x}$C alloy. We find that the variation of the lattice parameter as function of Rb composition exhibits a deviation from the Vegard's law of about 0.4 Å. The total energy results predict a ferromagnetic ordering for Sr-rich alloy, and antiferromagnetic ordering for RbC-rich alloy with a total magnetic moment ranging from 2 to 3$μ_\text{B}$ per cation. As for the parent compounds, RbC and SrC, the origin of magnetism arises from the polarization of the carbon $p$-orbitals. From the spin-polarized calculations, we note that the half-metallicity in the Rb$_{x}$Sr$_{1-x}$C alloy is confirmed for $x<0.875$. On the other hand, a direct band gap is observed in the semiconducting spin part, in contrast to the pure parent compounds.

cond-mat.mtrl-sci↗