Orbital hybridization in the spin-glass state of Mn-doped ZnTe

To gain insight into the spin-glass state of diluted magnetic semiconductors, we have examined the magnetic and electronic properties of Zn_1-xMn_xTe using density functional theory and magnetization measurements, where our measurements on the x = 0.43 and 0.55 samples demonstrate a clear spin-glass transition. Using a generalized gradient approximation, we investigate the electronic and magnetic properties for x = 0, 0.25, and 0.50 doping levels using the magnetic moment of Mn²⁺ as a guide for the dependence of the Hubbard onsite potential on the electronic structure. Simulations on both ferromagnetic (FM) and antiferromagnetic (AFM) configurations yield a distinct AFM ground state preference, where an onsite potential of up to 8 eV on the Mn 3d-orbitals is needed to harden the magnetic moment toward S = 5/2. From our analysis of the electronic structure evolution with doping and onsite potential, we confirm the semiconducting state of the material as well as show that Te-Mn pd-orbital hybridization is activated with the Mn doping above 25%, which is around the doping when the spin-glass transition begins to rise, which could be a precursor to the spin-glass state.