Low Electric Field Intensity and Thermotropic Tuning Surface Plasmon Band Shift of Gold Island Film by Liquid Crystals

By applying an electric field to nematic liquid crystals (LCs) to change the molecular alignment of LCs, we achieve feasible tuning of the localized surface plasmon resonance (LSPR) of novel gold island film immersed in the LCs, realizing the switching behavior of LSPR at low electric field intensity. In addition, we find that the liquid crystal can amplify the angle dependence of gold island film LSPR, which may provide a new method for research on the tiny and indistinct change of the gold nanoparticles' LSPR. At the same time, the LSPR can be used for detection of nematic LCs' thermal optic effect, especially when the temperature is around the clearing point. For the entire experimental procedure, self-assembly and experimental tests are simple and require only common laboratory supplies and equipment, and both of them are novel relative to previous studies, which help us further investigate coupling the metal nanoparticles with the LCs.