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Pseudogaps in the t-J model: Extended DMFT study

K. Haule·A. Rosch·J. Kroha·P. Wölfle
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Abstract

We investigate the highly incoherent regime of hole-doped 2d Mott-Hubbard insulators at moderately small doping and temperatures T>=0.1J, where J is the exchange coupling. Within an extended dynamical mean-field theory of the t-J model and a generalized non-crossing approximation we calculate the single-particle spectral function, the dynamical susceptibility, and thermodynamic and transport quantities. Short-ranged antiferromagnetic fluctuations lead to strongly incoherent single-particle dynamics, large entropy and large electrical resistivity. At low doping a pseudogap is found to open up both in the single-particle and the spin excitation spectra leading to a decrease in entropy and resistivity. The Hall coefficient changes sign to positive values upon lowering the doping level and increases inversely proportional to doping.

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K. Haule, A. Rosch, J. Kroha, P. Wölfle. 2003-04-04. Pseudogaps in the t-J model: Extended DMFT study. https://doi.org/10.1103/physrevb.68.155119

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