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Title: Magnetic field-induced Freedericksz transition in a chiral liquid crystal
A wedge cell made of homeotropically treated glass plates is filled with a chirally doped nematic liquid crystal. When a sufficiently large magnetic field is applied in the cell plane, a bend-like distortion occurs above a Fréedericksz threshold field H th . H th is reduced from the achiral case because of a field-induced bend distortion that facilitates a chiral twist distortion. Measurements of H th vs sample thickness are reported and compared favorably with a theoretical model presented herein. A further theoretical comparison is made between H th and the electric-field-induced transition in a geometry, exhibiting a 2π azimuthal degeneracy. The results may have technological implications in, for example, in-plane switching devices.  more » « less
Award ID(s):
1901797
NSF-PAR ID:
10402789
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
122
Issue:
13
ISSN:
0003-6951
Page Range / eLocation ID:
134101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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