Half Metallic Ferromagnetism and Transport Properties of Zinc Chalcogenides ZnX2Se4 (X = Ti,V, Cr) for Spintronic Applications

In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (T_c), spin polarization, half magnetic ferromagnetism and transport properties of ZnX₂Se₄ (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of T_c is perceived for ZnCr₂Se₄. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μ_B of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔE _crystal, exchange energies Δ _x(d), Δ _x (pd) and exchange constants (N_o α and N_o β ). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 10¹¹ W/mK²) among studied compounds.