| Abstract: | We have identified several important features in the neutron scattering data of cuprates that are difficult to explain 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 (A1g) symmetry and opposite sign in the bonding and antibonding electron bands formed within the Cu2O4 bilayers. The extended s wave has eight line nodes and changes sign when a node is crossed. This A1g pairing symmetry may be compatible with a charge-fluctuation-mediated pairing mechanism. |
