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Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Polar swimmers induce several phases in active nematics
Pranay Bimal Sampat1, Shradha Mishra1
1Department of Physics, Indian Institute of Technology (BHU), Varanasi, U.P. - 221005 India.
Physical Review. E
|September 16, 2021
Summary
Researchers modeled active nematics with polar particles, finding they form large structures and exhibit phase transitions. This work aids in detecting low densities of polar swimmers and controlling active nematic structures.
Area of Science:
- Physics
- Soft Matter Physics
- Active Matter
Background:
- Living liquid crystals, a class of active matter, involve swimming bacteria in passive nematics.
- Liquid crystal solutions show potential for bacterial trapping and detection.
- The study explores creating similar active matter systems using background nematics.
Purpose of the Study:
- To develop a minimal model for mixtures of polar particles in active nematics.
- To investigate the behavior and phase transitions of active nematics influenced by polar particles.
Main Methods:
- Development of a minimal theoretical model for active nematics with polar particles.
- Analysis of system behavior under varying polar particle densities.
Main Results:
- Active nematics exhibit high sensitivity to polar particles, forming large-scale structures even at low densities.
- Two distinct phase transitions are observed as polar particle density increases.
- Polar particles aggregate into aligned clusters that induce local order in the nematics.
Conclusions:
- The model demonstrates that active nematics can be designed to be sensitive to polar particles.
- The findings are applicable to detecting low concentrations of polar swimmers in active nematic systems.
- This research offers a pathway for designing and controlling structures within active nematics.
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