First-principles investigations of magnetic properties and Curie temperature in V-doped CdX (X = S, Se, and Te) compounds

The electronic structure and magnetic properties in zinc blende structure of Cd_1−xV_xX (X = S, Se, Te) with x  = 12.5 % diluted magnetic semiconductors (DMSs) have been investigated using the Generalized Gradient Approximation (GGA). The investigations were carried out employing the full potential-linearized augmented plane wave method (FP-LAPW) within Density Functional Theory (DFT), as implemented in the CASTEP code.

The hybridization between the p states of sulfur (S), selenium (Se), or tellurium (Te), and the 3d states of vanadium (V)., as revealed by the density of states, confirms the formation of antibonding states within the gap, which in turn stabilizes the ferromagnetic ground state associated with the double-exchange mechanism, the electronic structures exhibit half-metallic behavior for CdVTe and CdVS, while CdVSe shows semiconductor behavior for both spin channels at the same concentration (x = 12.5 %).

Furthermore, the total magnetic moment of Cd_1−xV_xX (X = S, Se, Te) compounds is primarily due to the V site, with very low contributions from Cd and the chalcogens (S, Se, Te). These compounds are robust ferromagnets with diverse band gap characteristics in their electronic structures, exhibiting 100 % spin polarization. This makes them suitable for potential applications in spintronics and in optoelectronic devices. Our findings provide a new opportunity for experimentalists to verify these predictions and explore the use of these materials in practical applications.