Transition from escaped to decomposed nematic defects, and vice versa
Adam L Susser1, Saša Harkai, Samo Kralj
1Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106, USA. rosenblatt@case.edu.
Soft Matter
|May 16, 2020
Summary
Escaped director profiles in nematic liquid crystals transform into surface defects and vice versa under electric fields. These transitions reveal topological pathways and co-rotating disclination lines.
Area of Science:
- Soft Matter Physics
- Liquid Crystal Science
- Topological Defects
Background:
- Nematic liquid crystals exhibit complex director profiles.
- Surface defects and bulk director structures are key features in liquid crystal physics.
Purpose of the Study:
- To investigate the transformation between escaped radial director profiles and surface defects in nematic liquid crystals.
- To explore the topological pathways governing these transitions.
- To analyze the behavior of associated disclination lines.
Main Methods:
- Experimental observation of director profile transitions.
- Numerical simulations of liquid crystal behavior.
- Analysis of topological pathways (discontinuous and continuous).
Main Results:
- An escaped radial director profile transitions to m = +1/2 surface defects at a threshold electric field.
- Half-integer defect pairs transform into a 3D escaping director profile at a threshold electric field.
- Disclination lines associated with m = +1/2 defects exhibit co-rotation under specific electric field and frequency conditions.
Conclusions:
- The study demonstrates controllable transitions between different topological states in liquid crystals.
- Topological pathways, both discontinuous and continuous, are identified for these transformations.
- Co-rotation of disclination lines offers insights into defect dynamics in nematic systems.
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