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Updated: Jul 10, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Three relaxation processes from an electric-field-induced polar structure in a columnar liquid crystalline urea
Yoshinori Okada1, Shohei Matsumoto, Fumito Araoka
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Abstract:
We have studied the polarization relaxation process after removing an applied electric field in the columnar hexagonal phase of N,N'-bis(3,4,5-trihexadecyloxyphenyl)urea by means of second-harmonic generation (SHG), switching current, and texture observation. Transient SHG and current associated by sudden field change show polarization switching associated with a molecular reorientation of about a few ms depending on the field strength. Furthermore, the texture observation reveals a column undulation process during 10 s to 1 min. The size of the polar domains was estimated to be 160 molecules by analyzing the field dependence of the SHG signal intensity on the basis of an Ising model.
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