In systems where electrons form both dispersive bands and small local spins, we show that changes in the spin configuration can tune the bands through a Lifshitz transition, resulting in a continuous metal-insulator transition associated with a progressive change in the Fermi surface topology. In contrast to the Mott-Hubbard and Slater pictures, this spin-driven Lifshitz transition appears in systems with a small electron-electron correlation and large hybridization. We show that this situation is realized in 5d distorted perovskites with half-filled t2g bands such as NaOsO3, 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.
Kim, B., Liu, P., Ergönenc, Z., Toschi, A., Khmelevskyi, S., Franchini, C. (2016). Lifshitz transition driven by spin fluctuations and spin-orbit renormalization in NaOsO3. PHYSICAL REVIEW. B, 94(24), 1-6 [10.1103/PhysRevB.94.241113].
Lifshitz transition driven by spin fluctuations and spin-orbit renormalization in NaOsO3
Franchini, Cesare
Writing – Review & Editing
2016
Abstract
In systems where electrons form both dispersive bands and small local spins, we show that changes in the spin configuration can tune the bands through a Lifshitz transition, resulting in a continuous metal-insulator transition associated with a progressive change in the Fermi surface topology. In contrast to the Mott-Hubbard and Slater pictures, this spin-driven Lifshitz transition appears in systems with a small electron-electron correlation and large hybridization. We show that this situation is realized in 5d distorted perovskites with half-filled t2g bands such as NaOsO3, 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.