Spin waves are propagating disturbances in the ordering of magnetic materials. These low-lying
collective excitations occur in magnetic lattices with
continuous symmetry. From the equivalent quasiparticle point of view, spin waves are known as
magnons, which are boson modes of the spin lattice that correspond roughly to the
phonon excitations of the nuclear lattice. As temperature is increased, the thermal excitation of spin waves reduces a
ferromagnet's spontaneous magnetization. The energies of spin waves are typically only in keeping with typical
Curie points at room temperature and below. The discussion of spin waves in
antiferromagnets is beyond the scope of this article.