The Neutron Peak in the Interlayer Tunneling Model of High Temperature   Superconductors
  Recent neutron scattering experiments in YBCO exhibit an unusual magnetic peak that appears only below the superconducting transition temperature. The experimental observations are explained within the context of the interlayer tunneling theory of high temperature superconductors. 
L. Yin, S. Chakravarty, P. W. Anderson