SPIRALS IN LIQUID-CRYSTALS IN A ROTATING MAGNETIC-FIELD

We have discovered spiral formation in nematic liquid crystal solitons under the influence of a rotating magnetic field. The shape of the spirals is well modeled by a rotating spiral of Archimedes, except in the immediate vicinity of the cores. The rotation of the driving magnetic field breaks the symmetry between counter rotating spirals, leading to differing wavelengths and spiral rotation rates. As the magnetic field rotation rate is decreased below a critical value, the wavelength diverges while the spiral rotation rate drops to zero. This divergence is related to a structural transition occurring within the solitons themselves. The spirals can be understood by examining the topology and symmetries of the solitons.