Spin susceptibility of two-dimensional transition-metal dichalcogenides

We have obtained analytical expressions for the q-dependent static spin susceptibility of monolayer transition-metal dichalcogenides, considering both the electron-doped and hole-doped cases. Our results are applied to calculate spin-related physical observables of monolayer MoS sub(2), focusing especially on in-plane/out-of-plane anisotropies. We find that the hole-mediated Ruderman-Kittel-Kasuya-Yosida exchange interaction for in-plane impurity-spin components decays with the power law R super(-[5/2]) as a function of distance R, which deviates from the R super(-2) power law normally exhibited by a two-dimensional Fermi liquid. In contrast, the out-of-plane spin response shows the familiar R super(-2) long-range behavior. We also use the spin susceptibility to define a collective g factor for hole-doped MoS sub(2) systems and discuss its density-dependent anisotropy.