Temperature dependence of dynamical spin susceptibility of transition metals

Abstract

A formalism is developed for the temperature-dependent dynamical spin susceptibility using a multiband scheme for transition metals. The imaginary part of the dynamical spin susceptibility is derived using the temperature-dependent Fermi distribution function. Kramers-Kronig relations are used to calculate the real part of the susceptibility function. The limiting cases are derived and discussed in the light of available theoretical results. The detailed calculations are carried out for ferromagnetic and paramagnetic nickel, palladium, and platinum for various values of momentum and energy transfer. It is found that the susceptibility decreases with the increase of temperature and the peaks at small values of momentum transfer are broadened and show a decrease in magnitude.