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Dynamical Mean-Field Theory for Doped Antiferromagnets

M. Fleck·A. I. Lichtenstein·A. M. Oles·L. Hedin·V. I. Anisimov
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Abstract

We have generalized the dynamical mean-field theory to study the doping dependence of the crossover from antiferromagnetic to short-range order modelled by an incommensurate spin density wave in the Hubbard model. The local selfenergy which includes spin fluctuations gives quasiparticle weights and spectral properties in good agreement with quantum Monte Carlo and exact diagonalization data in two dimensions. The spectra at finite doping are characterized by a Mott-Hubbard `gap' accompanied by a pseudogap induced by the local spin order.

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M. Fleck, A. I. Lichtenstein, A. M. Oles, L. Hedin, V. I. Anisimov. 1998-01-30. Dynamical Mean-Field Theory for Doped Antiferromagnets. https://doi.org/10.1103/physrevlett.80.2393

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