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DH(*) in chiral smectics under electric field.

C Meyer1, C Rabette2, P Gisse2

  • 1Laboratoire de Physique des Systèmes Complexes, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039, Amiens, France. claire.meyer@u-picardie.fr.

The European Physical Journal. E, Soft Matter
|July 29, 2016
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Summary

Researchers studied double helices (DH) in liquid crystals with chiral dopants. They found that electric fields can shrink DH structures and reduce their pitch, mimicking temperature changes.

Keywords:
Soft Matter: Liquid crystals

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Area of Science:

  • Liquid Crystal Physics
  • Chirality Studies
  • Soft Matter Science

Background:

  • Double helices (DH) form in liquid crystals doped with chiral molecules within the N-SmA temperature range.
  • Investigated systems included both left-handed and right-handed chiral dopants.

Purpose of the Study:

  • To investigate the behavior of double helices (DH) in chiral-doped liquid crystals.
  • To correlate the handedness of DH with the chirality of the mixture.
  • To study the effect of AC electric fields on DH structure and pitch.

Main Methods:

  • Experimental investigation of liquid crystal compounds.
  • Statistical analysis of double helix handedness.
  • Application of gradually increasing AC electric fields.

Main Results:

  • A correlation was observed between the handedness of DH and the chirality of the mixture.
  • Applying an AC electric field caused the cylinder circumscribing the DH to shrink.
  • This electric field-induced shrinking was accompanied by a reduction in the DH's pitch.

Conclusions:

  • The handedness of double helices in chiral-doped liquid crystals is influenced by mixture chirality.
  • AC electric fields can induce structural changes in double helices, including pitch reduction.
  • The observed electric field effect on DH pitch is analogous to temperature-induced changes.