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No well-defined remnant Fermi surface in Sr2CuO2Cl2

S. Haffner·D. M. Brammeier·C. G. Olson·L. L. Miller·D. W. Lynch
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Abstract

In angle-resolved photoelectron spectra of the antiferromagnetic insulators Ca2CuO2Cl2 and Sr2CuO2Cl2 a sharp drop of the spectral intensity of the lowest-lying band is observed along a line in k space equivalent to the Fermi surface of the optimally doped high-temperature superconductors. This was interpreted as a signature of the existence of a remnant Fermi surface in the insulating phase of the high-temperature superconductors. In this paper it is shown that the drop of the spectral intensity is not related to the spectral function but is a consequence of the electron-photon matrix element

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S. Haffner, D. M. Brammeier, C. G. Olson, L. L. Miller, D. W. Lynch. 2000-07-12. No well-defined remnant Fermi surface in Sr2CuO2Cl2. https://doi.org/10.1103/physrevb.63.212501

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