Dynamic properties of Kitaev Materials from time-dependent Majorana mean-field theory*

Recent years have seen a rapid increase in candidate "Kitaev materials"--potentially realizing the same gapless spin-liquid ground state as the exactly solvable Kitaev model on the honeycomb lattice. The solubility stems from rewriting the spins in terms of Majorana fermions leading naturally to a mean-field description that could be valid even in the presence of perturbations (e.g. magnetic field, Heisenberg coupling, etc.). Since real materials have such perturbations, computing their effect on observables may indicate which features survive and which will not. We show how time-dependent Majorana mean-field theory can be used to compute dynamical quantities directly, which agree with exact results at the Kitaev point, thereby potentially providing exact results in a neighborhood of parameter space around the Kitaev point.