Short-range order in metals above the Curie temperature

Abstract

We use the dynamic spin-fluctuation theory to study spin-density correlations in ferromagnetic metals above the Curie temperature. We calculate the spatial spin-correlation function, dynamic susceptibility and local magnetic moment. The dynamic susceptibility is related to the energy-integrated scattering cross-section (effective moment). Calculated effective and local moments of Fe and Ni are found in good agreement with results of polarized neutron scattering experiment over a wide temperature range. We find that short-range order remains up to distances of about 6 Å in Fe and 8 Å in Ni at TTC = 1.1 and slowly decreases with temperature.