Lehmann rotation of cholesteric droplets subjected to a temperature gradient: Role of the concentration of chiral molecules |
| |
Authors: | P Oswald |
| |
Institution: | (1) Laboratoire de Physique, école Normale Supérieure de Lyon, UMR 5672 of the CNRS, 46 Allée d’Italie, 69364 Lyon, France |
| |
Abstract: | We present a systematic study of the Lehmann rotation of cholesteric droplets subjected to a temperature gradient when the
concentration of chiral molecules is changed. The liquid crystal chosen is an eutectic mixture of 8CB and 8OCB doped with
a small amount of the chiral molecule R811. The angular velocity of the droplets strongly depend on their size and on the
concentration of chiral molecules. The Lehmann coefficient is estimated by using three different methods. Our results are
consistent with a Lehmann coefficient proportional to the concentration of chiral molecules. We additionally show the existence
of a critical size of the droplets below which they change texture and stop rotating. |
| |
Keywords: | PACS" target="_blank">PACS 61 30 -v Liquid crystals 65 40 De Thermal expansion thermomechanical effects 05 70 Ln Nonequilibrium and irreversible thermodynamics |
本文献已被 SpringerLink 等数据库收录! |