ABSTRACT

We propose that resonant inelastic X-ray scattering (RIXS) is an effective probe to detect the fractionalized excitations in two- and three-dimensional Kitaev spin liquids. While the non-spin-conserving RIXS responses are dominated by the gauge-flux excitations and reproduce the inelastic-neutron-scattering response, the spin-conserving (SC) RIXS response picks up the Majorana-fermion excitations and detects whether they are gapless at Dirac / Weyl points, nodal lines, or Fermi surfaces. As a signature of symmetry fractionalization, the SC RIXS response is suppressed around the Γ point for any Kitaev spin liquid on a bipartite lattice.