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arXiv · 0812.2697

Magnetic resonance in the cuprates -- exciton, plasmon, or π-mode

Zhihao Hao·Andrey V. Chubukov
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Abstract

We re-analyzed the issue whether the resonance peak observed in neutron scattering experiments on the cuprates is an exciton, a π-resonance, or a magnetic plasmon. We considered a toy model with on-cite Hubbard U and nearest-neighbor interactions in both charge and spin channels. We found that the resonance is predominantly an exciton, even if magnetic interaction is absent and d-wave pairing originates from attractive density-density interaction. Our results indicate that one cannot distinguish between spin and charge-mediated pairing interactions by just looking at the resonance peak in the dynamic spin susceptibility.

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Zhihao Hao, Andrey V. Chubukov. 2008-12-14. Magnetic resonance in the cuprates -- exciton, plasmon, or π-mode. https://arxiv.org/abs/0812.2697

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