Electro-optical and dielectric characterization of quantum dot doped polymer dispersed liquid crystal composite structures

In this thesis, dielectric, electro-optical, thermal and morphological characterization of the CdSeS/ZnS quantum dot (QD) doped polymer dispersed liquid crystal (PDLC) composite structure has been made. The dielectric properties of pure and QD doped PDLC composite structures have been investigated by dielectric/impedance spectroscopy technique depending on the frequency. The electro-optical properties of the samples were investigated using the electro-optical switching method. The phase transition temperatures of the pure and QD doped PDLC composite structures were measured using differential scanning calorimeter and the morphological structure using scanning electron microscope. Physical parameters such as real and imaginary parts of the complex dielectric constant, relaxation frequency, threshold voltage, relaxation time, response time, phase transition temperature of pure and QD doped PDLC composite structures were determined from the experimental results, and the morphological structures of the samples were obtained. The results showed that the QD additive significantly changed the physical properties of the PDLC composite structure and the PDLC/QD composite structure could be used in polymer and liquid crystal based opto-electronic device technology.