Spinwave and uniform precession linewidths in rare-earth substituted yttrium iron garnet

Abstract

The temperature dependence of the spinwave and uniform precession linewidths of yttrium iron garnet substituted with the order of one atomic percent of holmium, erbium, and europium was measured from 4.2°to 300°K. The data are compared to the theory of de Gennes, Kittel, and Portis which attributes the linewidth to the rapidly relaxing rare-earth ions. Although the theory qualitatively predicts the temperature dependence of the linewidth, the detailed behavior varies considerably in these materials and remains to be accounted for. A new technique is briefly described that is used for obtaining Hk from the main resonance nonlinear behavior of the susceptibility which avoids the detailed point measurements previously necessary. © 1962 The American Institute of Physics.