Theoretical study of resonant inelastic X-ray scattering spectrum in the Hubbard ladder

Tsutsui, Kenji; Toyama, Takami*; Maekawa, Sadamichi*

The spectra of the Cu -edge Resonant inelastic X-ray scattering on the ladder cuprates are calculated by using the exact diagonalization method. So far it has been suggested that the momentum-dependence of the spectra on the ladder system is related with the formation of the spin singlet in the ground state. It has also revealed that the stabilization of the spin singlet strongly depends on the sign of the diagonal hopping of holes. In this study, in order to clarify the relationship between the spectra and the formation of the singlet state, the dependence of the spectra on the diagonal hopping of holes is examined. We find that the feature of the spectra is actually changed by the hopping and conclude that the resonant inelastic X-ray scattering can reveal the formation of the spin singlet state in the ladder system.