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.

arXiv comment6 pages, 4 figures

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Cited by in corpus (6)

• Tutorial: A Beginner's Guide to Interpreting Magnetic Susceptibility Data with the Curie-Weiss Law
• Dual nature of 5$f$ electrons in the isostructural UM${}_2$Si${}_2$ family: from antiferro- to Pauli paramagnetism via hidden order
• Origin of Ising magnetism in Ca3Co2O6 unveiled by orbital imaging
• The Future of the Correlated Electron Problem
• Selective orbital imaging of excited states with x-ray spectroscopy: the example of $\alpha$-MnS
• Visualization of spin-orbit entangled 4f electrons in crystalline materials