Magnetic-field-induced structural change of a two-dimensional colloid of glycerol droplets on a nematic liquid-crystal surface

作者：Paek Sang In^*; Kim Song Jo; Kim Jong Hyun

来源：Physical Review E, 2013, 87(3): 032502.

DOI：10.1103/PhysRevE.87.032502

The structural changes of a two-dimensional colloidal crystal, consisting of glycerol droplets on a nematic liquid-crystal surface, due to a magnetic field applied parallel to the liquid-crystal surface, were observed and analyzed. The hexagonal lattice arrangement of glycerol droplets transformed into a smaller, anisotropic hexagonal-like lattice when the magnetic field was applied. The intermediate stage of the transition is influenced by the way in which the magnetic field is applied. When a sufficiently strong magnetic field is applied directly, the transition proceeds by passing through a random arrangement and then through a chainlike arrangement. With a gradually increasing magnetic field, the transition starts locally and extends throughout the entire region. The relaxation processes that occur once the field is switched off are very similar, irrespective of the manner in which the field is switched off. The relaxation begins at the outside and then extends to the central regions. No tendency to form a chainlike arrangement was observed during the relaxation process. The processes during switching on and off demonstrate a hysteresis with respect to the magnetic field strength. DOI: 10.1103/PhysRevE.87.032502

• 出版日期2013-3-5