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arXiv · 1905.02326

Pseudogap, van Hove Singularity, Maximum in Entropy and Specific Heat for Hole-Doped Mott Insulators

A. Reymbaut·S. Bergeron·R. Garioud·M. Thénault·M. Charlebois·P. Sémon·A. -M. S. Tremblay
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Abstract

The first indication of a pseudogap in cuprates came from a sudden decrease of NMR Knight shift at a doping-dependent temperature $T^*(\delta)$. Since then, experiments have found phase transitions at a lower $T^*_\text{phase}(\delta)$. Using plaquette cellular dynamical mean-field for the square-lattice Hubbard model at high temperature, where the results are reliable, we show that $T^*(\delta)$ shares many features of $T^*_\text{phase}(\delta)$. The remarkable agreement with several experiments, including quantum critical behavior of the electronic specific heat, supports the view that the pseudogap is controlled by a finite-doping extension of the Mott transition. We propose further experimental tests.

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A. Reymbaut, S. Bergeron, R. Garioud, M. Thénault, M. Charlebois, P. Sémon, A. -M. S. Tremblay. 2019-05-07. Pseudogap, van Hove Singularity, Maximum in Entropy and Specific Heat for Hole-Doped Mott Insulators. https://doi.org/10.1103/physrevresearch.1.023015

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