NEUTRON-SCATTERING FROM A D(X2-Y2)-WAVE SUPERCONDUCTOR WITH STRONG IMPURITY SCATTERING AND COULOMB CORRELATIONS

We calculate the spin susceptibility at and below Tc for a dx2-y2-wave superconductor with resonant impurity scattering and Coulomb correlations. Both the impurity scattering and the Coulomb correlations act to maintain peaks in the spin susceptibility, as a function of momentum, at the Brillouin zone edge. These peaks would otherwise be suppressed by the superconducting gap. At the highest impurity concentration considered here, the predicted amount of suppression of the imaginary part of the spin susceptibility in the superconducting state compared to the normal state is in qualitative agreement with results from recent magnetic neutron-scattering experiments on La1.86Sr0.14CuO4 for momentum values at the zone edge and along the zone diagonal. The predicted peak widths in the superconducting state, however, are narrower than those in the normal state, a narrowing which has not been observed experimentally. © 1995 The American Physical Society.