First-principles calculations to investigate vanadium-doped Li2Te compound for optoelectronic and spintronic applications

Abstract

The present study reports the structural, electronic, magnetic, and optical properties of vanadium-doped Li₂Te using the ab-initio simulations within the framework of density functional theory. To account for exchange-correlation effects, the PBE-GGA, PBE-GGA-mBJ, and PBE-GGA+U approximations were employed. Our findings reveal that the ground state of vanadium-doped Li₂Te is ferromagnetic, with the ferromagnetic behavior predominantly arising from strong spin-splitting effects on the d orbitals of vanadium atoms. The formation energy (\({E}_{F}\)​) was calculated to confirm the thermodynamic stability and alloying feasibility of the compound at zero temperature. The negative value of \({E}_{F}\)​ indicates favorable alloying stability. Electronic structure analysis demonstrates that the material exhibits half-metallic ferromagnetic behavior, characterized by 100% spin polarization at the Fermi level. This property makes it a promising candidate for spintronic applications. To further understand the magnetic interactions, the s(p)-d exchange coupling constants (\({N}_{0\alpha }\) and \({N}_{0\beta }\)) were computed, revealing significant exchange splitting effects in both conduction and valence bands. These findings provide comprehensive insights into the multifunctional properties of vanadium-doped Li₂Te, offering valuable references for its potential applications in next-generation spintronic devices.