A new era for liquid crystal research: Applications of liquid crystals in soft matter nano-, bio- and microtechnology

TLDR: In this paper, the authors review the physics aspects of the new research thrusts, in which liquid crystals often meet other types of soft condensed matter, such as polymers and colloidal nano- or microparticle dispersions.

About: This article is published in Current Applied Physics.The article was published on 2012-11-01 and is currently open access. It has received 587 citations till now. The article focuses on the topics: Liquid crystal & Soft matter.

Figures

Fig. 5. An example of the characteristic schlieren texture of nematic liquid crystals in degenerate planar alignment. The micrograph is of a lyotropic nematic formed by discshaped micelles, but the same type of texture can be formed by any type of achiral nematic in degenerate planar geometry. From [13].

Fig. 6. Graphical definitions of the three elementary director field deformations splay, twist and bend, together with their corresponding terms in the elastic free energy and their respective elastic constants K1, K2 and K3. The drawings illustrate how each deformation can be produced in practice by encapsulating a nematic between flat substrates, the insides of which are prepared such as to ensure uniform planar or homeotropic director orientation at the substrate (the preferred director is indicated with a thick double-headed arrow). Redrawn after de Gennes and Prost [23].

Fig. 12. Cartoon illustrating the two main approaches to produce nanoporous silica using hexagonal lyotropic liquid crystal templates. Reprinted with permission (from reference [37]. Copyright (2007) American Chemical Society).

Fig. 16. (a) Schematic of the cholesteric droplets functioning as a medium for mirrorless lasing. (b) Polarizing microscopy image of a short-pitch cholesteric droplet reflecting red light. (c) Lasing from the droplet when pumped with an external pulsed laser source. Adapted with permission (Copyright 2010 Optical Society of America) from reference [230]. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 20. Cryo-TEM images of soft nanoparticles containing reversed bicontinuous (aed), sponge (eef) and reversed hexagonal (geh) lyotropic liquid crystal phases. Reprinted with permission from reference [320]. Copyright (2005) American Chemical Society.

Fig. 7. Examples of disclinations of magnitude 1/2, 1 and 2, of positive and negative sign, in a planar-aligned nematic. For the s ¼ 1/2 and s ¼ 1 cases, polarizing micrographs are provided as illustrations how these disclinations can be recognized in the polarizing microscope. Note that the sign of the disclination cannot easily be determined from a single micrograph.

Frequently asked questions

Q1. What are the contributions in "A new era for liquid crystal research: applications of liquid crystals in soft matter nano-, bio- and microtechnology" ?

Today this full breadth of the liquid crystalline state of matter is becoming increasingly recognized and numerous new and exciting lines of research are being opened up. The authors review this exciting development, focusing primarily on the physics aspects of the new research thrusts, in which liquid crystals e thermotropic as well as lyotropic e often meet other types of soft matter, such as polymers and colloidal nanoor microparticle dispersions. The authors then discuss a selection of promising new directions, starting with liquid crystals for organic electronics, followed by nanotemplating and nanoparticle organization using liquid crystals, liquid crystal colloids ( where the liquid crystal can constitute either the continuous phase or the disperse phase, as droplets or shells ) and their potential in e. g. photonics and metamaterials, liquid crystal-functionalized polymer fibers, liquid crystal elastomer actuators, ending with a brief overview of activities focusing on liquid crystals in biology, food science and pharmacology. 

Q2. What are the future works mentioned in the paper "A new era for liquid crystal research: applications of liquid crystals in soft matter nano-, bio- and microtechnology" ?

In any case, this is a very exciting development, outlining a bright and rich future for the open-minded liquid crystal scientist or other soft matter nano-/microtechnology researcher with an interest in liquid crystals.