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The magnetic resonance in high-temperature superconductors: Evidence for an extended s-wave pairing symmetrysymmetry

Guo-meng Zhao
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Abstract

We have identified several important features in the neutron scattering data of cuprates, which are difficult to be explained in terms of d-wave and isotropic s-wave order parameters. Alternatively, we show that the neutron data are in quantitative agreement with an order parameter that has an extended s-wave (A_1g) symmetry and opposite sign in the bonding and antibonding electron bands formed within the Cu_{2}O_{4} bilayers. The extended s-wave has eight line nodes and change signs when a node is crossed. This A_1g pairing symmetry may be compatible with a charge fluctuation mediated pairing mechanism.

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Guo-meng Zhao. 2004-01-08. The magnetic resonance in high-temperature superconductors: Evidence for an extended s-wave pairing symmetrysymmetry. https://arxiv.org/abs/cond-mat/0302566

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