Defects in Nematic Liquid Crystals

S=-1/2 Defect Line
  • n(theta)=(sin(theta/2), cos(theta/2))
  • Winding number -1/2

Winding Number Can't Jump

  • Singular Core
  • Defect Lines Can't End
  • Nematic is Greek for Thread
Also Hedgehog Point Defect: Rare

This research was paid for by THE US GOVERNMENT by the NSF.

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Sethna's Research 90-94
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Last modified: November 2, 1995

James P. Sethna,

Statistical Mechanics: Entropy, Order Parameters, and Complexity, now available at Oxford University Press (USA, Europe).