Ferromagnetism, half-metallicity and spin-polarised electronic structures characterisation insights in Ca_{1− x}Ti_xO

Khedidja Korichi (1) , Bendouma Doumi (1) , Allel Mokaddem , Adlane Sayede (2) , Abdelkader Tadjer

1 University of Saida
2 UCCS Équipe Couches Minces & Nanomatériaux

In this study, we have computed the structural, electronic and half-metallic ferromagnetic properties of Ca_1−xTi_xO compounds at concentrations x = 0.125, 0.25, 0.5 and 0.75 by employing the first-principle approaches of density functional theory. The generalised gradient approximation of Wu and Cohen (GGA-WC) is used to calculate the structural parameters, whereas the electronic structures and magnetic properties are characterised by the accurate Tran–Blaha-modified Becke–Johnson potential (TB-mBJ). The lattice constant, bulk modulus and indirect gap of CaO are in good agreement with other theoretical and experimental results. The Ca_0.25Ti_0.75O at x = 0.75 has metallic ferromagnetic nature. The Ca_0.875Ti_0.125O, Ca_0.75Ti_0.25O and Ca_0.50Ti_0.50O compounds have total magnetic moments of 2 μB per Ti atom with a half-metallic character, a spin polarisation of 100% and a large half-metallic gap of 1.345 eV for x = 0.125. Therefore, the Ca_1−xTi_xO material with a low concentration of Ti is a true half-metallic ferromagnet and seems to be a promising candidate for semiconductor spintronics.

Domaines: Matériaux; Chimie; Physique [physics]

Khedidja Korichi, Bendouma Doumi, Allel Mokaddem, Adlane Sayede, Abdelkader Tadjer. Ferromagnetism, half-metallicity and spin-polarised electronic structures characterisation insights in Ca_{1− x}Ti_xO. Philosophical Magazine, 2020, 100 (9), pp.1172-1190. ⟨10.1080/14786435.2020.1723812⟩. ⟨hal-03205778⟩