Hierarchical elasticity of bimesogenic liquid crystals with twist-bend nematic phase
作者： Chang-Jun Yun , M. R. Vengatesan , Jagdish K. Vij , Jang-Kun Song
DOI: 10.1063/1.4919065
关键词: Biaxial nematic 、 Materials science 、 Condensed matter physics 、 Extrapolation 、 Transition temperature 、 Phase transition 、 Elasticity (economics) 、 Liquid crystal 、 Atmospheric temperature range 、 Twist 、 Optics
摘要: In 2001, Dozov predicted that twist-bend nematic phase can be spontaneously formed when K33 2, and this has recently been discovered in bimesogens. To verify Dozov's hypothesis, we have measured precisely the temperature dependence of elastic constants CB7CB entire range close to transition by combing Freedericksz threshold methods for a twist an in-plane switching cells. Anomalous changes K22 K33 are observed across transition. The elasticity estimated via extrapolation data high region seems fully satisfy hypothesis although vicinity exhibit opposite trends. This explained general nature hierarchical system where macroscopic is governed mostly distortion higher level structure.
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