Orbital polarization in itinerant magnets

Area of Science:

• Solid State Physics
• Computational Materials Science
• Quantum Chemistry

Background:

• Orbital polarization (OP) is crucial for understanding magnetic properties in materials.
• Accurate calculation of OP is challenging, often requiring empirical parameters.
• Existing methods like random-phase approximation (RPA) have limitations for strongly correlated systems.

Purpose of the Study:

• To introduce a parameter-free computational scheme for calculating orbital polarization in metals.
• To improve the accuracy of orbital magnetization and magnetic anisotropy energy calculations.
• To provide a robust method applicable to transition-metal and actinide compounds.

Main Methods:

• Utilizing a strong-coupling limit for screened Coulomb interactions within the random-phase approximation (RPA).
• Incorporating local-field corrections to restore spin polarization from local-spin-density approximation for itinerant magnets.
• Computing orbital polarization as a self-energy correction using the static GW method.

Main Results:

• The proposed method offers a parameter-free calculation of orbital polarization.
• It systematically improves orbital magnetization and magnetic anisotropy energies.
• The approach enhances the accuracy of theoretical predictions for magnetic materials.

Conclusions:

• The parameter-free GW-based scheme provides a more accurate and reliable way to compute orbital polarization.
• This method advances the understanding and prediction of magnetic properties in metals.
• It is particularly beneficial for transition-metal and actinide-based magnetic materials.