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arXiv · 2001.00019

Not all doped Mott insulators have a pseudogap: key role of van Hove singularities

Wei Wu·Mathias S. Scheurer·Michel Ferrero·Antoine Georges
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Abstract

The Mott insulating phase of the parent compounds is frequently taken as starting point for the underdoped high-$T_c$ cuprate superconductors. In particular, the pseudogap state is often considered as deriving from the Mott insulator. In this work, we systematically investigate different weakly-doped Mott insulators on the square and triangular lattice to clarify the relationship between the pseudogap and Mottness. We show that doping a two-dimensional Mott insulator does not necessarily lead to a pseudogap phase. Despite its inherent strong-coupling nature, we find that the existence or absence of a pseudogap depends sensitively on non-interacting band parameters and identify the crucial role played by the van Hove singularities of the system. Motivated by a SU(2) gauge theory for the pseudogap state, we propose and verify numerically a simple equation that governs the evolution of characteristic features in the electronic scattering rate.

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Wei Wu, Mathias S. Scheurer, Michel Ferrero, Antoine Georges. 2019-12-31. Not all doped Mott insulators have a pseudogap: key role of van Hove singularities. https://doi.org/10.1103/physrevresearch.2.033067

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