SURPRISING DYNAMICS OF SOME CHOLESTERIC LIQUID-CRYSTAL PATTERNS

Under homeotropic anchoring conditions, the first order nematic-choles teric phase transition gives rise to localized spatial patterns called cholesteric fingers. In this Letter we describe a new equilibrium str ucture which, to our knowledge, has never been reported either numeric ally or analytically, and we investigate its dynamics. This chiral pat tern, which has broken the parity symmetry, is found to move when subm itted to an ac electric voltage or to a white noise. Our result may ex plain, at least qualitatively, the recent observations of spontaneous spiral wave formations in cholesteric liquid crystal under the applica tion of an ac electric voltage.