Light-Responsive Microstructures in Droplets of the Twist-Bend Nematic Phase.

We report on the structure and optical manipulation of the director configurations in emulsions of liquid-crystalline droplets of a compound exhibiting the nematic (N) and the twist-bend nematic (N) phases. We demonstrate a decrease in the ratio of the bent elastic constant K to the splay constant K by nearly 2 orders of magnitude with decreasing temperature in the N phase. The director structures in liquid-crystal droplets doped with a photoswitchable surfactant without and under ultraviolet (UV) light are discussed in light of the strong elastic anisotropy of the investigated compound.

Photoluminescence of CdSe/ZnS quantum dots in nematic liquid crystals in electric fields.

We have experimentally investigated the effect of the reorientation of a nematic liquid crystal (LC) in an electric field on the photoluminescence (PL) of CdSe/ZnS semiconductor quantum dots (QDs). To the LC with positive dielectric anisotropy, 1 wt % QDs with a core diameter of 5 nm was added. We compared the change of PL intensity and decay times of QDs in LC cells with initially planar or vertically orientated molecules, i.

Hybrid structures based on gold nanoparticles and semiconductor quantum dots for biosensor applications.

Background: The luminescence amplification of semiconductor quantum dots (QD) in the presence of self-assembled gold nanoparticles (Au NPs) is one of way for creating biosensors with highly efficient transduction.

Aims: The objective of this study was to fabricate the hybrid structures based on semiconductor CdSe/ZnS QDs and Au NP arrays and to use them as biosensors of protein.

Methods: In this paper, the hybrid structures based on CdSe/ZnS QDs and Au NP arrays were fabricated using spin coating processes.