Exchange Effects in Ferromagnetic Resonance with Nonlocal Conductivity

Abstract

A solution is obtained for the surface impedance of a ferromagnetic metal with a wave-number-dependent conductivity function, by an extension of the method of Reuter and Sondheimer. Computed curves are given for some specific cases. It is concluded that exchange effects are large under suitable low-temperature conditions, but there are too many unknown parameters to allow a very accurate value of the exchange constant to be deduced from resonance experiments. For extreme anomalous conductivity, exchange effects depend on the combination $\left(\mathrm{exchange}\mathrm{constant}\right)\times {\left(\mathrm{conductivity}\right)}^{\frac{2}{3}}$.