Theory of the neutron scattering cross section in spin-glasses

Using mean-field theory we compute the frequency-integrated neutron cross section I(q,T) for spin-glasses. We find, as observed experimentally, that the temperature of the maximum of I(q,T) depends on the momentum transfer q and is different from the freezing temperature Tc at which the susceptibility (q,T) has a cusp. These results suggest that recent neutron scattering experiments are consistent with a sharp phase transition at a single temperature Tc in spin-glasses. © 1978 The American Physical Society.