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arXiv · 1601.03310

Lifshitz transition driven by spin fluctuations and spin-orbit renormalization in NaOsO$_3$

Bongjae Kim·Peitao Liu·Zeynep Ergönenc·Alessandro Toschi·Sergii Khmelevskyi·Cesare Franchini
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Abstract

In systems where electrons form both dispersive bands and small local spins, we show that changes of the spin configuration can tune the bands through a Lifshitz transition, resulting in a continuous metal-insulator transition associated with a progressive change of the Fermi surface topology. In contrast to a Mott-Hubbard and Slater pictures, this spin-driven Lifshitz transition appears in systems with small electron-electron correlation and large hybridization. We show that this situation is realized in 5$d$ distorted perovskites with an half-filled $t_{2g}$ bands such as NaOsO$_3$, where the strong $p-d$ hybridization reduces the local moment, and spin-orbit coupling causes a large renormalization of the electronic mobility. This weakens the role of electronic correlations and drives the system towards an itinerant magnetic regime which enables spin-fluctuations.

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Bongjae Kim, Peitao Liu, Zeynep Ergönenc, Alessandro Toschi, Sergii Khmelevskyi, Cesare Franchini. 2016-01-13. Lifshitz transition driven by spin fluctuations and spin-orbit renormalization in NaOsO$_3$. https://doi.org/10.1103/physrevb.94.241113

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