Spin‐Waves in Randomly Diluted Ferromagnets and Antiferromagnets

Publisher Website
Google Scholar
Abstract
We consider the spin‐wave excitations of magnetic crystals in which a fraction of the magnetic spins are replaced randomly by non magnetic impurities. A simple Heisenberg nearest neighbor exchange is assumed. The treatment follows the usual linear spin wave approximation and so is only appropriate for low temperatures. However the disorder is treated exactly by use of a computer simulation technique for finite, but large models. We present results for simple, body centered and face centered cubic as well as the simple square lattice. Results for both ferromagnets and antiferromagnets are presented and show contrasting behaviors. The spectra of ferromagnets remain essentially continuous before breaking into many fine peaks below the percolation concentration. The spectra of the antiferromagnets develop large peaks, with some complex substructure, even well above the percolation limit.

This publication has 0 references indexed in Scilit: