Spin waves in HoZn

Abstract
The spin wave spectrum of the equiatomic HoZn compound (CsCl structure) has been studied at 4.2K. Two branches were followed along the principal symmetry directions. The data were analysed following a Green function formalism to obtain the Fourier transform of interactions. Ferromagnetic interactions with first and third neighbours are dominant. The precise energy location of dispersion curves requires, in addition to one-ion crystal field parameters, the inclusion of biquadratic exchange terms in the initial Hamiltonian.