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arXiv · 1910.05151

Osmates on the verge of a Hund's-Mott transition: The different fates of NaOsO$_3$ and LiOsO$_3$

Daniel Springer·Bongjae Kim·Peitao Liu·Sergii Khmelevskyi·Severino Adler·Massimo Capone·Giorgio Sangiovanni·Cesare Franchini·Alessandro Toschi
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Abstract

We clarify the origin of the strikingly different spectroscopic properties of the chemically similar compounds NaOsO$_3$ and LiOsO$_3$. Our first-principle many-body analysis demonstrates that the highly sensitive physics of these two materials is controlled by their proximity to an adjacent Hund's-Mott insulating phase. In mildly correlated $5d$ oxides, this physics is triggered by the {\sl cooperative} action of intraorbital repulsion and Hund's exchange in half-filled $t_{2g}$ outer-shells. Small material-specific details hence result in an extremely sharp change of the electronic mobility, explaining the surprisingly different properties of the paramagnetic high-temperature phases of the two compounds.

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Daniel Springer, Bongjae Kim, Peitao Liu, Sergii Khmelevskyi, Severino Adler, Massimo Capone, Giorgio Sangiovanni, Cesare Franchini, Alessandro Toschi. 2019-10-11. Osmates on the verge of a Hund's-Mott transition: The different fates of NaOsO$_3$ and LiOsO$_3$. https://doi.org/10.1103/physrevlett.125.166402

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