Physics at Interfaces

Research - Hydrodynamics


Liquid crystals in external fields

Instabilities in liquid crystalline droplets:
We study nematic liquid crystalline droplets coexisting with isotropic domains when the temperature is kept constant within the phase transition interval. When nematic liquid crystalline droplets are dispersed in isotropic media, their shape and internal director configuration interacts with applied electric fields. Liquid crystals have a small but finite conductivity, which depends on both the phase and the orientation. As in other leaky dielectric systems, ac electric field may induce either prolate or oblate deformations of the nematic droplets. Due to the extremely low surface tension of nematic-isotropic interface, one can obtain substantial deformations which are easily visible under the microscope.

  • G. K. Auernhammer, J. Zhao, B. Ullrich, and D. Vollmer;
    Frequency dependent deformation of liquid crystal droplets in an external electric field;
    Eur. Phys. J. E, (2009), DOI: 10.1140/epje/i2009-10538-y.