Unprecedented Dual Alignment Mode and Freedericksz Transition in Planar Nematic Liquid Crystal Cells Doped with Gold Nanoclusters

Abstract

We demonstrate that alkylthiol‐capped gold nanoclusters doped into nematic liquid crystals (N‐LCs) with positive dielectric anisotropy give rise to an unprecedented dual alignment mode and electro‐optical response, which has a potential impact on current liquid crystal (LC) display technologies and N‐LC optical‐biosensor design. By fine‐tuning experimental conditions (temperature, electric field, and alignment), N‐LCs doped with gold nanoclusters can be aligned and electrically reoriented either like N‐LCs with a positive dielectric anisotropy in a planar cell or, alternatively, as N‐LCs with a negative dielectric anisotropy in a homeotropic cell, both at lower threshold voltages than the pure N‐LC.

The Physicochemical and Nanotechnological Approaches to Creation of “Rigid” DNA Nanoconstructions

“…Though first nanoparticles used in such systems were carbon nanotubes, nano-Au or nanoparticles with gold "core" [20,21] are often utilized nowadays. As a result of such processing not only the physicochemical properties of low molecular mass liquid crystals can be varied [22][23][24] but one can get a specific ordering of nanoparticles in liquid crystals [25].…”

Fast algorithms for liquid crystal modelling

“…22 In these cases the liquid crystal alignment is dominated by elastic and electrostatic forces with the dopants acting to alter rather than dominate the properties of the liquid crystal. Their effect, however, can be significant [23][24][25] and may lead to applications related to plasmon tuning in self-assembled structures 26,27 or tunable metamaterials. 28 The existence of an invariant manifold for the Q-tensor equations in the absence of defects can also be used to model in a computationally efficient way nematic liquid crystals doped with nanoparticles.…”

Dielectric and Electro-Optical Properties of Ceramic Nanoparticles Doped Liquid Crystals

“…The interaction between nanomaterials and LCs depends upon the various factors like nature of dispersing materials, refractive index of nanomaterials and LCs, shape and size of nanomaterials, concentration of nanomaterials into LC host, density, physical and chemical properties and applied electric field parameters [23][24][25]. Dispersion of nanoparticle in LCs has shown considerable improvement in the existing properties of LC material, exhibiting many special characteristics such as frequency modulation, enhancement of the dielectric anisotropy and birefringence, reduced threshold voltage and induced vertical alignment [26][27][28][29][30][31][32]. Recently, the modifications of the physical properties of liquid crystals by doping nanoparticles have received much attention for the enhancement of the performance of LC electro-optical devices.…”