Scattering of Polarized Light on Magnetically Aligned Particles in Multipole Magnetic Fields

The theory of polarized light scattering on aligned colloidal magnetic particles (Fe3O4) in multipole magnetic fields is given. With the assumption of an anisotropic light scattering process, the azimuthal location of the observed scattering pattern can be explained. The observed eightfold symmetry in the scattering pattern of a sextupole magnetic field and the twelvefold symmetry of an octupole field can be interpreted as consequences of the field configuration symmetry in a sextupole and an octupole, respectively. The temperature dependence of the scattering pattern intensity can be explained as a change in the number of scattering centers. It is assumed that the number of aligned scattering centers is given by the Langevin function as a function of the temperature of the colloidal solution. Some applications of this theory, such as the magnetic center location in multipoles, are discussed.