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Video recording of the
seminar
December 9 (Wednesday), 2015
17:00
Oleg Lavrentovich
Kent State
University, OH, USA
Statics and dynamics of colloidal particles in liquid crystals
Behavior of small particles in fluids have fascinated
scientist for centuries. Phenomena such
as Brownian motion, sedimentation, and electrophoresis continue to inspire
cutting-edge research and innovation.
The fluid in which the colloidal particles move is typically isotropic,
such as water or a polymer solution.
When the particles are placed in an anisotropic fluid, a liquid crystal,
their behavior changes, because of the appearance of long-range elastic
interactions [1]. Recently, our group
started to explore the dynamics of colloids in liquid crystal environment [2]. The study reveals that liquid crystals change
dramatically both the static and dynamic behavior of colloids, enabling
levitation of particles, anomalous Brownian diffusion regimes [2], and new
mechanisms of eletrokinetics [3,4].
Adding an active component to a liquid crystal, such as moving bacteria,
allows one to trace a cascade of transitions from equilibrium to
non-equilibrium orientational patterns [5].
The new phenomena are rooted in anisotropy of the liquid crystal
properties, such as surface tension and elasticity, electric conductivity and
dielectric permittivity [6,7].
1 P. Poulin, H. Stark, T.C. Lubensky, and D.A. Weitz, Science 275, 1770 (1997).
2 O.D. Lavrentovich, Soft Matter 10, 1264 (2014).
4 O.D. Lavrentovich, I. Lazo and O.P. Pishnyak, Nature 467, 947 (2010).
6 S. Zhou, A. Sokolov, O.D. Lavrentovich and I.S. Aranson, PNAS 111, 1265 (2014).
7 A. Sokolov, S. Zhou, O.D. Lavrentovich, and I.S. Aranson, Phys. Rev. E 91, 013009 (2015)
8 C. Peng, Y. Guo, C. Conklin, J. Vinals, S.V. Shiyanovskii, Q.H. Wei, and O.D. Lavrentovich, Phys. Rev. E 92, 052502 (2015).
About the speaker
Oleg D. Lavrentovich is a Trustees Research Professor at the Liquid Crystal Institute at Kent State University. He received his Ph.D. (1984) and Doctor of Science (1990) degrees in Physics and Mathematics from the Ukrainian Academy of Sciences. In 1992 he joined the Liquid Crystal Institute as a Senior Research Fellow. He served as the director of institute in 2003-2011. Lavrentovich held visiting appointments at the University P. et M. Curie, University Denis Diderot in France and other universities. He is the editor of Liquid Crystals Reviews (Taylor & Francis), member of the Editorial Boards of Liquid Crystals, Condensed Matter Physics, Ukrainian Journal of Physics and Advisor of the Kent State University SPIE Student Chapter.