Constraining spin directions in density functional theory calculations by imposing a local magnetic field

By constraining the directions of magnetic moments in first-principles calculations, one can investigate the physical properties of desirable magnetic structures and extract parameters of magnetic interactions. However, the current methods for constraining the directions of magnetism in first-principles calculations may lead to quenched magnetic moments mathematically and practically. In this paper, we propose a method to constrain the spin directions in both collinear and noncollinear cases by imposing a local parallel magnetic field. The effectiveness of this method is confirmed by performing calculations on GdMn2O5 and MnSi by using a modified VASP package. Through these examples, we find that by adding an external parallel local magnetic field, we are able to constrain the spin directions more efficiently than existing methods.

Automated summary

In this paper, a method of constraining spin directions by imposing a local parallel magnetic field is proposed. It is found that this method is more efficient in constraining spin directions than existing methods.