Spin-orbit crossed susceptibility in topological Dirac semimetals

TL;DR

This paper theoretically investigates the spin-orbit crossed susceptibility in topological Dirac semimetals, revealing its dependence on Dirac point separation and anisotropic behavior, with implications for understanding orbital and spin magnetization.

Contribution

It introduces a theoretical framework for the spin-orbit crossed susceptibility in Dirac semimetals, highlighting its proportionality to Dirac point separation and anisotropic characteristics.

Findings

Spin-orbit crossed susceptibility is proportional to Dirac point separation.

Orbital magnetization is induced only along the rotational symmetry axis.

Spin susceptibility is anisotropic and induced perpendicular to the symmetry axis.

Abstract

We theoretically study the spin-orbit crossed susceptibility of topological Dirac semimetals. Because of strong spin-orbit coupling, the orbital motion of electrons is modulated by Zeeman coupling, which contributes to orbital magnetization. We find that the spin-orbit crossed susceptibility is proportional to the separation of the Dirac points and it is highly anisotropic. The orbital magnetization is induced only along the rotational symmetry axis. We also study the conventional spin susceptibility. The spin susceptibility exhibits anisotropy and the spin magnetization is induced only along the perpendicular to the rotational symmetry axis in contrast to the spin-orbit crossed susceptibility. We quantitatively compare the two susceptibilities and find that they can be comparable.