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arXiv · cond-mat/0506364

Correlated band structure and the ground-state phase diagram in high-Tc cuprates

Abstract

We review results obtained with a recently proposed variational cluster approach (VCA) for the competition between d-wave superconductivity (dSC) and antiferromagnetism (AF) in the high-Tc cuprates. Comparing the single-particle spectra of a two-dimensional Hubbard model with quantum Monte-Carlo (QMC) and experimental data, we verify that the VCA correctly treats the low-energy excitations. The cluster calculations reproduce the overall ground-state phase diagram of the high-temperature superconductors both for electron- and hole-doping. In particular, they include salient features such as the enhanced robustness of the AF state in case of electron doping. For electron- but also for hole-doping, we clearly identify a tendency to phase separation into a mixed AF-dSC phase at low and a pure dSC-phase at high doping.

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BibTeXRIS

Werner Hanke, Markus Aichhorn, Enrico Arrigoni, Michael Potthoff. 2005-06-15. Correlated band structure and the ground-state phase diagram in high-Tc cuprates. https://doi.org/10.1016/j.physb.2006.01.139

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