CuGeO3 and CuO by respectively elastic and inelastic polarized neutrons

Polarization analysis permitted to verify very promptly that the plane of the helix in the incommensurate phase of CuO was not (a*,c*) as first proposed but another one containing without equivoque the b*-axis.Inelastic polarization analysis under applied magnetic field permitted to study the triplet magnon-like mode of spin-Peierls CuGeO3. This mode splits in three, as expected. Intensities of inelastic neutron scattering measurements with polarization analysis have been collected in both spin-flip and nonspin-flip channels. This Zeeman splitting revealed that two out of the three processes are purely spin-flip excitations, while the third undisplaced one is a nonspin-flip process in which the neutron conserves its spin orientation