Science Daily March 2, 2022 Researchers at the University of Chicago have introduced the concept of using topological defects in active matter to perform logic operations. When an extensile active stress in a nematic liquid crystal is turned on, +1/2 defects can self-propel, in analogy to electron transport under a voltage gradient. By relying on hydrodynamic simulations of active nematics, they demonstrated that patterns of activity, when combined with surfaces imparting certain orientations, can be used to control the formation and transport of +1/2 defects. They also showed that asymmetric high- and low-activity patterns can be used to create effective […]
Category Archives: Liquid crystal
Scientists develop novel ‘shapeshifting’ liquid crystal
Phys.org October 19, 2021 A team of researchers in the US (Case Western reserve University, Tufts University, Sandia National Laboratory) manipulated an “orientable Newtonian liquid,” in this case to a nematic liquid crystal that behaves predictably, i.e., linearly, when an outside stimulus is applied. They forced the liquid crystal/air interface to change shape merely by exploiting the orientability of the molecules that comprise the liquid crystal by placing a patterned substrate on the opposite side of a thin nematic film. By doing so, they were able to control the alignment of molecules throughout the material which resulted in the appearance […]
Liquid crystals could help deflect laser pointer attacks on aircraft
Optics.org April 2, 2019 Researchers at Lewis University, Illinois, focused on the polarization and absorbance properties of liquid crystal materials to block incoming laser light. To decrease the intensity of incoming laser light, the liquid crystal N-(4-Methoxybenzylidene)-4-butylaniline was deposited between two pieces of conductive indium tin oxide-coated glass. The test cell can decrease up to 80 percent of incoming laser light by transitioning from its transparent, liquid phase to its opaque, pseudo-crystalline phase, with the cell being able to return to its transparent phase in less than three seconds. The phase change is controlled by an electric current applied to […]