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arXiv:cond-mat/9606198

Short-Range Antiferromagnetic Correlations and the Photoemission Spectrum

Bulut, N.

Published Jun 26, 1996• 0 citations
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Abstract

We present Quantum Monte Carlo results on the antiferromagnetic correlations and the one-electron excitations of the doped two-dimensional Hubbard model. These results are helpful in interpreting the NMR, neutron scattering and photoemission experiments on the layered cuprates.
DOI
10.48550/arxiv.cond-mat/9606198

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A consequence of strong antiferromagnetic correlations in models of high-Tc cuprates is the appearance in photoemission (PES) calculations of considerable more weight above the Fermi momentum pF{\rm {\bf p}_F }pF​ than expected for non-interacting electrons. This effect, first discussed by Kampf and Schrieffer (Phys. Rev. {\bf B 41}, 6399 (1990)) under the name of ``shadow bands'', is here analyzed in the two dimensional Hubbard and t-J models using Monte Carlo and exact diagonalization techniques. It is concluded that for underdoped compounds weight above pF{\rm {\bf p}_F }pF​ could be observable in experimental PES data, while in the overdoped regime it will be likely hidden in the experimental background. In the intermediate region the signal is weak. Our results are thus compatible with recent experimental data by Aebi et al. (Phys. Rev. Lett. {\bf 72}, 2757 (1994)) for Bi2212 at optimal doping. However, to definitely prove the existence of this effect in the cuprates, experiments in the underdoped regime are necessary.