Dong Chen, featured ILCC liquid crystal artist, April 2013
Dong Chen graduated from the Liquid Crystal Materials Research Center (LCMRC) at the University of Colorado at Boulder (CU) and now is a Postdoc in the same group under the guidance of Prof. Noel A. Clark. His research areas mainly focus on characterizing the microstructures of various liquid crystal phases, especially using freeze fracture transmission electron microscopy (FFTEM) which enables direct visualization of the layer structure of smectic liquid crystals, with a Ph.D. thesis titled “Nanostructures of Liquid Crystal Phases”. In 2006, he received his B.S. degree of applied physics with a thesis about “Investigating the interplay of magnetic and ferroelectricity in magneticelectric multiferroics by substituting the Mn site of DyMnO3 with Cr ion” from University of Science and Technology of China (USTC) in China. After two years’ study at CU, he got the M.S. degree after passing a comprehensive exam on the topic of “Investigation of the Faraday instability” in 2009.
Depolarized transmission light microscope image of 95% 8CB/NOBOW mixture (c, the wt% of 8CB). The sample is filled in a 4μm cell with planar alignment. The picture is taken at 30°C with crossed polarizer and analyzer (size: 1.95mmX2.55mm). Mixtures of NOBOW with 8CB form a single, homogeneous phase only in the high temperature, isotropic range. At lower temperatures, the NOBOW B4 phase-separates into a network of helical nanofilaments, leaving the 8CB to fill the interstitial spaces. In this picture, the NOBOW B4 phase forms the dendritic/fractal texture through the chirality-preserving growth of the helical nanofilaments and the 8CB is in the SmA phase made of typical focal conics. Interestingly, under the microscope, the dendritic/fractal texture of the NOBOW B4 phase appears to smoothly go along the focal conic surface of the 8CB SmA phase.
Jury comment: This striking image is unique in that it depicts two immiscible phases - the 8CB SmA phase and the P-9-O-PIMB (NOBOW) helical nanofilament (HNF) phase, where the NOBOW is present at low concentration. The HNF phase can be easily seen forming dendritic supra-HNF structures superimposed on the SmA focal conic texture. Full disclosure: Dr. Dong is part of the Boulder LC group, and the jury has the privilege of working with him. This image, however, was unknown to the jury prior to it's appearance in the list of submitted LC picture images.