Soft-Mode Turbulence in Electroconvection of Nematics

Optical Characterization of Electroconvection in Nematics

We describe non-standard techniques for optical studies of electrocon-vection structures in nematics. The time-resolved textures in the high frequency oscillatory regime are analyzed and compared with results of optical simulations. Conclusions on the relation between director pattern and optical texture are drawn. Using an additional phase plate in the optical setup , we monitor director twist...

Spatio-temporal Analysis of Electroconvection in Nematics

für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...

Correlation Functions in Homeotropic Nematics: Non-Exponential Relaxation of Soft-Mode Turbulence

Glassy dynamics in relaxation of soft-mode turbulence.

The autocorrelation function of pattern fluctuation is used to study soft-mode turbulence (SMT), a spatiotemporal chaos observed in homeotropic nematics. We show that relaxation near the electroconvection threshold deviates from the exponential. To describe this relaxation, we propose a compressed exponential appearing in dynamics of glass-forming liquids. Our findings suggest that coherent mot...

Electroconvection with and without the Carr-Helfrich effect in a series of nematics

Experimental electroconvection investigations on four homologs with negative dielectric anisotropy εa and conductivity anisotropies σa of various signs (the relative σ̂a σa σ ranges from -0.6 to +0.3) are reported. The homolog with positive conductivity anisotropy follows the predictions of the standard theoretical model, while the homolog with negative σa shows a new phenomenon i.e. non-standar...