Orbital Engineering in Nickelate Heterostructures Driven by Anisotropic Oxygen Hybridization rather than Orbital Energy Levels
Orbital Engineering in Nickelate Heterostructures Driven by Anisotropic Oxygen Hybridization rather than Orbital Energy Levels
Resonant inelastic x-ray scattering is used to investigate the electronic origin of orbital polarization in nickelate heterostructures taking $\mathrm{LaTiO_3-LaNiO_3-3x(LaAlO_3)}$, a system with exceptionally large polarization, as a model system. We find that heterostructuring generates only minor changes in the Ni $3d$ orbital energy levels, contradicting the often-invoked picture in which …