Spin-wave renormalization by mobile holes in a two-dimensional quantum antiferromagnet

Authors

  • Georges Krier,

    1. Theoretische Physik, Universität des Saarlandes, D-66041 Saarbrücken, Germany
    Current affiliation:
    1. Max-Planck Institut für Festkörperphysik, Heisenbergstraße 1, D-70506 Stuttgart, Germany
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  • Günther Meissner

    1. Theoretische Physik, Universität des Saarlandes, D-66041 Saarbrücken, Germany
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Abstract

The coupling of antiferromagnetic spin excitations and propagating holes has been studied theoretically on a square lattice in order to investigate the dependence of antiferromagnetic order on hole doping, being of relevance, e.g., for the Cu–3 d9 system in antiferromagnetic CuO2-planes of high-Tc superconductors. An effective Hamiltonian has been used, which results from a 2D Hubbard model (hopping integral t) with holes and with strong on-site Coulomb repulsion U. Bare antiferromagnetic excitations and holes with energies of the same order of magnitude t2/U are interacting via a coupling term being proportional to t and allowing holes to hop by emitting and absorbing spinwaves. In terms of a self-consistent one-loop approximation the renormalization of the spectral function both of holes and antiferromagnetic spin excitations are calculated.

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