ONE-DIMENSIONAL PATTERNS AND WAVELENGTH SELECTION IN MAGNETIC FLUIDS

present the first experimental evidence of macroscopic one-dimensional patterns and forced wavelength selection in magnetic colloidal suspen sions in an oscillating magnetic field. The resulting dramatic enhance ment of the domain growth kinetics gives rise to concentration pattern s composed of a main periodic structure and similar periodic substruct ures, which have a wave vector increasing with the excitation frequenc y, and decreasing with the suspension concentration.