Magnetic response in topological Dirac semimetals

In recent condensed matter physics, topological semimetals attract many researchers. Topological Dirac semimetals are one of them and realized in Na₃Bi and Cd₃As₂. The topological Dirac semimetals have pairs of band touching points called Dirac points. We theoretically study the spin-orbital susceptibility of the topological Dirac semimetal. In strong spin-orbit coupling systems, orbital magnetization is induced by Zeeman coupling. We find the spin-orbital susceptibility of the topological Dirac semimetal can be comparable to the conventional spin magnetic susceptibility.