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Updated: Jan 22, 2026
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Simulations of electric-field-induced turbulence and negative viscosity in conductive nematic liquid crystals
Hiroshi Orihara1, Tomoyuki Nagaya2
1Hokkaido University, Research Institute for Electronic Science, Sapporo 001-0021, Japan.
Abstract:
Experiments using a rotational rheometer have demonstrated that the apparent viscosity becomes negative under the electric-field-induced turbulent state of conductive nematic liquid crystals [Orihara et al., Phys. Rev. E 99, 012701 (2019)10.1103/PhysRevE.99.012701; F. Kobayashi et al., Phys. Rev. E 101, 022702 (2020)10.1103/PhysRevE.101.022702]. When the upper rotating plate of the rheometer is left free, spontaneous rotation-that is, spontaneous shear flow-has also been observed. In this study, we reproduce these phenomena through three-dimensional simulations based on continuum theory. The simulations reveal characteristic velocity, director, and stress fields in the negative-viscosity state. Furthermore, they clarify the interplay between topological defects (disclinations) and space charges which drive the turbulence.
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