Quantitative analysis of nematic director reorientation dynamics studied by time-resolved spectroscopic ellipsometry

The director reorientation dynamics of the nematic liquid crystal (NLC) filled in a conventional sandwich cell was demonstrated by means of time-resolved spectroscopic ellipsometry (TRSE). By using a dye-doped NLC, the transient behavior of the NLC director near the alignment layer as well as that in the bulk can be observed clearly without using any special cavity such as a waveguide. It is shown that the observed transient change of the ellipsometric angles, which corresponds to the director reorientation dynamics, can be completely reproduced by the numerical simulation based on the Frank's elastic continuum theory. From these numerical and experimental results, it is emphasized that TRSE is a potential instrument to analyze the director reorientation dynamics of NLC.