Helix unwinding of doped cholesteric liquid crystals

Yip, W. C.; Kwok, H. S.
January 2001
Applied Physics Letters;1/22/2001, Vol. 78 Issue 4, p425
Academic Journal
By introducing benzoyl-benzene into a cholesteric liquid crystal, the helix unwinding voltage was reduced. This reduction was roughly proportional to the concentration of the dopant and was present for driving frequencies across the audio spectrum. It is believed that this voltage reduction is primarily due to a perturbation of the intermolecular coupling in the liquid crystal mixture. It was found that so long as the long-range order was not destroyed, the helix unwinding voltage could be reduced by as much as 24% at 60 Hz.


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