Local Refractive Index Measurement on a Cholesteric Liquid Crystal Using the Surface Plasmon Technique

The surface plasmon technique is used to measure the local refractive indices in the quasi-nematic layers of a cholesteric liquid crystal with an accuracy of about 10−4. The local linear birefringence reflecting the orientational order of molecules in the quasi-nematic layers shows a temperature dependence characteristic of a nematic and in good agreement with the theory of nematic ordering.