Abstract
Attenuated total reflection is an important method in examining the excitation of surface plasmons. We use Kretcshmann-Raether configuration to study this interesting phenomenon and determine the refractive index of dielectric substance, liquid crystal, next to a 550A silver film that is coated on the incline surface of a right-angled prism of refractive index 1.7782. Varying the electric field applied to the liquid crystal, we alter the orientation of the liquid crystal, i.e., alter the effective refractive index of liquid crystal contacted to silver film and hence the condition of enhancement of surface plasmons was changed. Applying the sensitive response of excited position of surface plasmons due to refractive index of dielectric medium, experimental result show that the orientations of liquid crystal near interface were almost unaltered. On the other hand, we simulate the alignment of liquid crystal by Monte Carlo method, determining the response time of nemectic liquid crystal under different temperature and electric field applied.