Spherical neutron spin polarimetry of anisotropic magnetic fluctuations in UO2 -: art. no. 184411

The anisotropy of magnetic fluctuations propagating along the symmetric directions Delta, Sigma, and Gamma in the ordered phase of uranium dioxide has been studied by applying the spherical neutron-spin polarimetry technique to inelastic neutron scattering. The dependence of fluctuation amplitudes and directions as a function of the quasiparticle wave vector q has been investigated along the main crystallographic directions. The observed behavior is discussed in relation to the spin dynamics of the 3-k transverse magnetic structure. The observed polarization behavior of the spin waves, and in particular the acoustic mode, is shown to be a natural consequence of the transverse 3-k magnetic structure.