Efficient calculation of magnetocrystalline anisotropy using symmetry-aware Wannier Hamiltonian<!-- notionvc: 86e8ec28-a098-49bb-8ed6-854499d2f259 -->

We have developed an efficient method for accurately calculating magnetic anisotropy. This method involves creating a Wannier basis tight-binding model using first-principles calculations and considering the crystal and spin symmetry. Furthermore, this approach employs time-reversal symmetry to distinguish magnetization from spin-orbit interactions, making it easy to generate Hamiltonians with magnetization oriented in any direction without requiring additional DFT calculations each time.

To validate our method, we apply it to calculate the magnetocrystalline anisotropy energy (MCAE) of L1₀-type FePt and FeNi. Our results show excellent agreement with previous studies on the chemical potential dependence of the MCAE. Additionally, we obtain the full angle dependence of the MCAE on the direction of magnetization. These findings provide a deeper understanding of magnetic properties and offer potential applications in various fields.