Orbital-selective electronic excitations in iron arsenides revealed by simulated nonresonant inelastic x-ray scattering

Nonresonant inelastic x-ray scattering (NIXS) is a possible tool to detect charge excitations in electron systems. In addition, multipole transitions at high-momentum-transfer regions open a newpossibility to determine orbital-selective electronic excitations in multiorbital itinerant 3d electron systems. As a theoretical example, we choose the antiferromagnetic state of iron arsenides and demonstrate that the orbital-selective excitations are detectable by choosing appropriate momentum transfer in NIXS. We propose that both NIXS and resonant inelastic x-ray scattering are complementary to each other for fully understanding the nature of orbital excitations in multiorbital itinerant electron systems.