Electronic structure and magnetic properties of Dy-doped Bi2Te3

Highlights: • Electronic and magnetic character, and the magnetic anisotropy in the rare earth based materials are investigated. • DFT+U+HIA method accurately describes the spin and orbital magnetic moments, and the magnetic anisotropy for SmCo₅. • The method is applied to theoretical investigation of Dy-doped Bi₂Te₃ topological insulator, and the positive magnetic anisotropy is predicted. • The experimental resonant photoemission spectra of Dy-doped Bi₂Te₃ are well reproduced by the calculations. -- Abstract: The electronic and magnetic character, and the magnetic anisotropy in practically important magnetic materials containing the rare earth elements are investigated making use of the correlated band theory implemented as a combination of the relativistic density functional theory with the Anderson impurity model (DFT+U+HIA). First, we demonstrate that DFT+U+HIA provides a good description of the electronic structure, spin and orbital magnetic moments, and the magnetic anisotropy for SmCo₅ magnet with 4f⁵-like Sm³⁺ shell. Further, the method is applied to theoretical investigation of Dy-doped Bi₂Te₃ topological insulator. For both ferro- and anti-ferromagnetic Dy-planes in Bi₂Te₃ we found the in-gap flat f-bands located at the top of the valence band of Bi₂Te₃. The positive uniaxial MAE is predicted for (Dy_xBi_1−x)₂Te₃ with x = 0.33. The experimental resonant photoemission spectra are well reproduced by the calculations. These studies can be important to explore the potential use of rare-earth doped topological insulators in the low-power spintronic devises.