Direct imaging of orbitals in quantum materials

Abstract

The spectacular physical properties of quantum materials based on transition metal, rare earth, and actinide elements continue to challenge our comprehension of solid state physics and chemistry. The electronic states of these materials are dominated by the $d$ and $f$ wave functions intertwined with the strong band formation of the solid. In order to estimate which wave functions contribute to the ground state formation, we have had to rely, until now, on theoretical calculations combined with spectroscopy. Here we show that $s$-core-level non-resonant inelastic x-ray scattering ($s$-NIXS) can directly image the active orbital in real space, without the necessity of any modeling. The power and accuracy of this new technique is shown using the text-book example, x${}^2$-y${}^2$/3$z^2$-r${}^2$ orbital of the Ni${}^{2+}$ ion in NiO single crystal.

6 pages, 4 figures

References in corpus (8)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Controlling orbital moment and spin orientation in CoO layers by strain
• Non-resonant inelastic x-ray scattering involving excitonic excitations
• High multipole transitions in NIXS: valence and hybridization in 4f systems
• Determining the crystal-field ground state in rare earth Heavy Fermion materials using soft-x-ray absorption spectroscopy
• 4$f$ crystal field ground state of the strongly correlated topological insulator SmB${}_6$
• Determining the in-plane orientation of the ground-state orbital of CeCu2Si2
• Direct bulk sensitive probe of 5f symmetry in URu2Si2

Cited by in corpus (2)

• Origin of Ising magnetism in Ca3Co2O6 unveiled by orbital imaging
• Selective orbital imaging of excited states with x-ray spectroscopy: the example of $\alpha$-MnS