Spin waves in the ferrimagnetic phase of NdCu2

Abstract The spin wave dispersion relation in the ferrimagnetic phase F1 of NdCu 2 has been measured by means of inelastic neutron scattering. In a -direction the expected six dispersion branches could be determined. The spin wave dispersion is compared to that of the ferromagnetic phase F3. In F1 the magnetic Brillouin zone is only one-third of that in F3 introducing additional symmetry conditions for the dispersion relation. The experimental results agree well with these conditions.