Electric-field-induced dynamics in radial liquid crystal droplets studied by multiphoton-excited fluorescence microscopy

Xie, Aifang; Higgins, Daniel A.
May 2004
Applied Physics Letters;5/17/2004, Vol. 84 Issue 20, p4014
Academic Journal
Time-resolved multiphoton-excited fluorescence microscopy is used to study electric-field-induced reorientation dynamics in single liquid crystal (LC) droplets within polymer-dispersed liquid crystal films. Films comprised of nematic LC dispersed in a poly(isobutyl methacrylate) matrix are characterized. An electric field is applied laterally across each droplet, using two parallel copper wires embedded in the film. Three-photon excited fluorescence images are recorded with 200 µs time resolution as the field is modulated on and off. Dramatic spatial variations in the time scales for orientational relaxation within individual droplets are observed. These effects are attributed to polymer/LC interfacial interactions and relaxation of the LC through a transient, metastable organizational state.


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