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Electronic state of a doped Mott-Hubbard insulator at finite temperatures studied using the dynamical mean-field theory

A. Camjayi·R. Chitra·M. J. Rozenberg
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Abstract

We study the electronic state of the doped Mott-Hubbard insulator within Dynamical Mean Field Theory. The evolution of the finite temperature spectral functions as a function of doping show large redistributions of spectral weight in both antiferromagnetic and paramagnetic phases. In particular, a metallic antiferromagnetic state is obtained with a low frequency Slater-splitted quasiparticle peak coexisting with Hubbard bands. In the high temperature paramagnetic metallic phase, upon reducing doping, the system has a crossover through a ``bad metal'' state characterized by an anomalous shift of the quasiparticle peak away from the Fermi energy. We find that the {\it charge} compressibility of the antiferromagnetic metal is dramatically enhanced upon approaching the second order Néel line.

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A. Camjayi, R. Chitra, M. J. Rozenberg. 2006-04-06. Electronic state of a doped Mott-Hubbard insulator at finite temperatures studied using the dynamical mean-field theory. https://doi.org/10.1103/physrevb.73.041103

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