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arXiv · 0811.0552

Theory of two-particle excitations and the magnetic susceptibility in high-Tc cuprate superconductors

S. Brehm·E. Arrigoni·M. Aichhorn·W. Hanke
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Abstract

Two-particle (2-p) excitations such as spin and charge excitations play a key role in high-Tc cuprate superconductors (HTSC). On the basis of a parameter-free theory, which extends the Variational Cluster Approach (a recently developed embedded cluster method) to 2-p excitations, the magnetic excitations of HTSC are shown to be reproduced for a Hubbard model within the relevant strong-coupling regime. In particular, the resonance mode in the underdoped regime, its intensity and "hour-glass" dispersion are in good overall agreement with experiments.

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S. Brehm, E. Arrigoni, M. Aichhorn, W. Hanke. 2010-02-11. Theory of two-particle excitations and the magnetic susceptibility in high-Tc cuprate superconductors. https://doi.org/10.1209/0295-5075%2F89%2F27005

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