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arXiv · 2011.02906

From basic properties to the Mott design of correlated delafossites

Frank Lechermann
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Abstract

The natural-heterostructure concept realized in delafossites highlights these layered oxides. While metallic, band- or Mott-insulating character may be associated with individual layers, inter-layer coupling still plays a decisive role. We review the correlated electronic structure of PdCoO$_2$, PdCrO$_2$ and AgCrO$_2$, showing that layer-entangled electronic states can deviate from standard classifications of interacting systems. This finding opens up possibilities for materials design in a subtle Mott-critical regime. Manipulated Hidden-Mott physics, correlation-induced semimetallicity, or Dirac/flat-band dispersions in a Mott background are emerging features. Together with achievements in the experimental preparation, this inaugurates an exciting research field in the arena of correlated materials.

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Frank Lechermann. 2020-11-05. From basic properties to the Mott design of correlated delafossites. https://doi.org/10.1038/s41524-021-00586-6

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