Collective Modes and Electronic Raman Scattering in the Cuprates
  While the low frequency electronic Raman response in the superconducting state of the cuprates can be largely understood in terms of a d-wave energy gap, a long standing problem has been an explanation for the spectra observed in A_{1g} polarization orientations. We present calculations which suggest that the peak position of the observed A_{1g} spectra is due to a collective spin fluctuation mode. 
F. Venturini, U. Michelucci, T.P. Devereaux, A.P. Kampf