Density of Spin Wave States for Disordered Cubic Ferromagnets

The interest in ferromagnetism in amorphous materials which first surfaced in a paper by Gubanov1 was stimulated in the mid sixties by the discovery of several amorphous ferromagnets in various laboratories.2 There has been some theoretical response to these experimental observations by Handyich3 who used molecular field theory to show a decreased spontaneous magnetization arising from structure fluctuations and by Montgomery and coworkers4 who applied a Green’s function method to a disordered spin one-half Heisenberg ferromagnet of simple cubic topology. The present paper expands this latter work to show the effects of disorder in higher spin systems of single cubic (sc), body-centered cubic (bcc) and face-centered cubic (fcc) symmetry.