Pseudogap, van Hove singularity, maximum in entropy, and specific heat for hole-doped Mott insulators

Abstract

The first indication of a pseudogap in cuprates came from a sudden decrease of the NMR Knight shift at a doping-dependent temperature T^{*}(δ). Since then, experiments have found phase transitions at a lower T_{phase}^{*}(δ). Using plaquette cellular dynamical mean field for the square-lattice Hubbard model at high temperature, where the results are reliable, we show that T^{*}(δ) shares many features of T_{phase}^{*}(δ). 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.