Resonant inelastic x-ray scattering study of vector chiral ordered kagome antiferromagnet

We study the resonant inelastic x-ray scattering (RIXS) features of vector chiral ordered kagome antiferromagnets. Utilizing a group theoretical formalism that respects lattice site symmetry, we calculated the L -edge magnon contribution for the vesignieite compound BaCu₃V₂O₈(OH)₂. We show that polarization dependence of the L -edge RIXS spectrum can be used to track magnon branches. We predict a non-zero L -edge signal in the non-cross π-π polarization channel. At the K -edge, we derived the two-site effective RIXS and Raman scattering operator for two-magnon excitation in vesignieite using the Shastry-Shraiman formalism. Our derivation considers spin-orbit coupling effects in virtual hopping processes. We find vector chiral correlation (four-spin) contribution that is proportional to the RIXS spectrum. Our scattering operator formalism can be applied to a host of non-collinear non-coplanar magnetic materials at both the L and K -edge. We demonstrate that vector chiral correlations can be accessed by RIXS experiments.