Liquid crystal nanoscience, a field exploring the mutually beneficial combination of the unique properties of nanoscale materials and fluid, yet ordered liquid crystalline phases, is increasingly focusing on semiconductor quantum dots. In one major research thrust, the anisotropic properties of the liquid crystal host are sought to facilitate the assembly of quantum dots into arrays, in another, both size-and shape-dependent optical and electronic properties of quantum dots are used to manipulate optical, electro-optical and alignment properties of liquid crystalline materials. This feature article reviews recent accomplishments and new insights in this fascinating area of soft matter nanocomposites including work from our laboratory on a series of CdSe and CdTe quantum dots as additives in nematic liquid crystal hosts.

Ink‐jet printing of monolayer‐capped gold nanoparticles is introduced as a versatile and highly efficient means to pattern the alignment of nematic liquid crystals. Any homeotropic alignment patterns can be created quickly ranging in size from 30 μm (850 dpi) to several square inches, with high accuracy that does not deteriorate with time. Depending on the alignment underlayer, intermediate configurations between homeotropic and homogeneous are also feasible. Nematic liquid crystals with both positive and negative dielectric anisotropy can be switched by applying a DC or AC electric field in the printed vertical domains with the substrate configuration determining the electro‐optic response.

Ink‐jet printing of monolayer‐capped nanoparticles is introduced as a versatile and highly efficient means to pattern the alignment of nematic liquid crystals. As discussed by Torsten Hegmann and co‐workers on page 257, any homeotropic alignment patterns that can be switched by applying AC or DC electric field can quickly be created with high accuracy ranging in size from a few micron (>850 dpi) to several square inch.

The liquid crystal alignment method described here provides uniform orientation of otherwise difficult-to-align smectic-A liquid crystal materials lacking a nematic phase. The smectic-A phase is grown in the presence of a 10-20 K/mm temperature gradient from an air bubble located within a cell by a photolithographically defined channel in the cell substrates. We obtain uniform layer alignment in millimeter-wide smectic regions at growth rates below about 0.05 m / s even though there is a tendency for spontaneous nucleation of focal-conic defects at higher growth rates once the width of the smectic-A region exceeds the critical value of about 20 m.

SiO x alignment layers have been shown to allow defect-free SmC ‫ء‬ devices with near optimum bistable orientation of the director. In this paper we investigate the effect of the thickness of this type of alignment layer on the required amplitude of an applied voltage pulse to cause bistable switching. The results of an experimental investigation and simple model are presented. We find that for thicker layers, the amplitude is controlled by the voltage drop across the alignment layers and by the effect of polar interactions between the liquid crystal ͑LC͒ and the alignment layers. For thin alignment layers the amplitude is weakly dependent on the details of the alignment layer, being more strongly influenced by the properties of the LC material.

An array of electrically controlled adaptive microlenses produced as a liquid crystal cell with microlens-profiled aligning surface is presented. Measurements of microlens’ adaptivity are quantitatively explained by a proposed theoretical model. Details of microlens array production and characterization are presented along with the achievable electrically controlled focal length changes for nematic liquid crystals 5CB and ZLI-4801. Effects related to liquid crystal reorientation on the curved surface of the spherical lenses are discussed.

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We investigated the effect of the surface alignment layer on the analog switching properties of ferroelectric liquid crystals. Using a liquid crystal that does not exhibit a nematic phase allowed us to obtain alignment of the smectic layers independent of the surface alignment layer used. This allowed to test various alignment layers that have not been tested before, and to demonstrate improved performance