First-principles prediction of ferromagnetic half-Heusler LiMnTe for spintronic applications.

First-principles calculations were performed to investigate the structural stability, magnetism, electronic structure, and intrinsic hall transport of half-Heusler LiMnTe. Among the considered phases, ferromagnetic β-LiMnTe is identified as the ground-state configuration, with an equilibrium lattice constant of 6.39 Å and an integer magnetic moment of 4.00 µ B per f.u. Its energetic, mechanical, and dynamical stability is supported by the negative formation energy, satisfaction of the Born-Huang criteria, and absence of imaginary phonon modes. At the PBE level, the Mn-d-dominated electronic structure yields 99.68% spin polarization and nearly half-metallic behavior, whereas DFT + U largely preserves the total magnetic moment but reduces the polarization at larger U eff. Strong nearest-neighbor Mn-Mn exchange stabilizes ferromagnetic ordering and yields a predicted Curie temperature of 352 K. Spin-orbit-coupled Berry-curvature and spin-Berry-curvature hot spots near the Fermi level produce sizable anomalous and spin Hall conductivities of -683.61 S cm-1 and -322.35 (ħ/e) S cm-1, respectively. Strain further tunes the spin polarization and Hall responses while preserving ferromagnetism. These results identify β-LiMnTe as a promising candidate for spintronic applications.