Single and double orbital excitations probed by resonant inelastic x-ray scattering.
The dispersion of the elusive elementary excitations of orbital ordered systems, orbitons, has escaped detection so far. The recent advances in resonant inelastic x-ray scattering (RIXS) techniques have made it, in principle, a powerful new probe of orbiton dynamics. We compute the detailed traces that orbitons leave in RIXS for an e{g} orbital ordered system, using the ultrashort core-hole lifetime expansion for RIXS. We observe that both single- and double-orbiton excitations are allowed, where the former, at lower energy, have sharper features. The rich energy- and momentum-dependent intensity variations that we observe make clear that RIXS is an ideal method to identify and map out orbiton dispersions.
Institute-Lorentz for Theoretical Physics, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands.
Filomena
F
Forte
Luuk J P
LJ
Ament
Jeroen
J
van den Brink