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arXiv · 2409.17268

LiV2O4: Hund-Assisted Orbital-Selective Mottness

Martin Grundner·Fabian B. Kugler·Olivier Parcollet·Ulrich Schollwöck·Antoine Georges·Alexander Hampel
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Abstract

We show that the remarkably small Fermi-liquid coherence scale and large effective mass observed in LiV$_2$O$_4$ are due to the proximity of a Hund-assisted orbital-selective Mott state. Our work is based on an ab initio dynamical mean-field approach, combining several quantum impurity solvers to capture the physics from high to very low temperature. We find that the Hund coupling plays a crucial role in rearranging the orbital populations and in generating the heavy mass and low coherence scale. The latter is found to be approximately 1-2 Kelvin, even though the most correlated orbital is found to be significantly doped ~10% away from half-filling. A flat quasiparticle band appears near the Fermi level as a result of the strong electronic correlations. Finally, we discuss our results in comparison to experiments.

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Martin Grundner, Fabian B. Kugler, Olivier Parcollet, Ulrich Schollwöck, Antoine Georges, Alexander Hampel. 2025-07-08. LiV2O4: Hund-Assisted Orbital-Selective Mottness. https://doi.org/10.1103/m42m-t4dm

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