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Magnetic properties of the three-band Hubbard model

Th. Maier·M. B. Zoelfl·Th. Pruschke·J. Keller
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Abstract

We present magnetic properties of the three-band Hubbard model in the para- and antiferromagnetic phase on a hypercubic lattice calculated with the Dynamical Mean-Field Theory (DMFT). To allow for solutions with broken spin-symmetry we extended the approach to lattices with AB-like structure. Above a critical sublattice magnetization m_d=0.5 one can observe rich structures in the spectral-functions similar to the t-J model which can be related to the well known bound states for one hole in the Neel-background. In addition to the one-particle properties we discuss the static spin-susceptiblity in the paramagnetic state at the points q=0 and q=(pi,pi,pi,...) for different dopings delta. The delta-T-phase-diagram exhibits an enhanced stability of the antiferromagnetic state for electron-doped systems in comparison to hole-doped. This asymmetry in the phase diagram is in qualitative agreement with experiments for high-T_c materials.

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Th. Maier, M. B. Zoelfl, Th. Pruschke, J. Keller. 1998-09-15. Magnetic properties of the three-band Hubbard model. https://doi.org/10.1016/s0921-4526(98)01021-7

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