Action of fields on captive disclination loops

  • Mallory Dazza
  • Rui Cabeça
  • Simon Čopar
  • Maria Helena Godinho
  • Pawel Pieranski
Regular Article


We report on two effects observed in experiments with captive disclination loops on polymeric fibers immersed in nematics and submitted to electric and/or magnetic fields. We show that the magnetic field oblique to a fiber with axial or helicoidal anchoring on its surface induces translation of disclination loops. Fields orthogonal to fibers with helicoidal anchoring make disclination loops rotate around the field direction. In the linear regime of this last chirogyral effect, the angle of rotation is proportional to the helix wave vector and its sense unveils the chirality of the helix. We propose a model explaining the origin and all features of these two effects.

Graphical abstract


Soft Matter: Liquid crystals 


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Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Mallory Dazza
    • 1
    • 2
  • Rui Cabeça
    • 3
  • Simon Čopar
    • 4
  • Maria Helena Godinho
    • 3
  • Pawel Pieranski
    • 1
  1. 1.Laboratoire de Physique des SolidesUniversité Paris-SudOrsayFrance
  2. 2.École normale supérieure de CachanCachanFrance
  3. 3.CENIMAT, Faculdade de Ciências e TecnologiaUniversidade Nova de LisboaCaparicaPortugal
  4. 4.Faculty of Mathematics and PhysicsUniversity of LjubljanaLjubljanaSlovenia

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