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Magnetic Excitations in Bilayer High-Temperature Superconductors with Stripe Correlations

G. S. Uhrig·K. P. Schmidt·M. Grüninger
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Abstract

The universal behaviour of the magnetic excitations in high-temperature superconductors is described in a model with static stripes retaining only the localized spin degrees of freedom. The stripes are represented by a model of coupled two-leg spin ladders. We start from the results obtained previously by continuous unitary transformations for an isolated spin ladder. A quantitative description of neutron scattering data is reached, using a model for a single cuprate layer with well established values of the exchange coupling constants. The neutron resonance peak is explained in terms of a saddle point in the dispersion of the magnetic excitations. Here we make predictions for bilayer systems with in-phase or out-of-phase stripe correlations. The results may serve as a guide for future experimental analyses.

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G. S. Uhrig, K. P. Schmidt, M. Grüninger. 2005-02-21. Magnetic Excitations in Bilayer High-Temperature Superconductors with Stripe Correlations. https://arxiv.org/abs/cond-mat/0502460

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