Chemotaxis mediated interactions can stabilize the hydrodynamic instabilities in active suspensions

Area of Science:

• Physics
• Chemistry
• Materials Science

Background:

• Active suspensions of polar swimmers typically exhibit instabilities in ordered phases due to long-wavelength hydrodynamics.
• Dissolved chemical molecules are common in wet active systems but their stabilizing role is often overlooked.

Purpose of the Study:

• To investigate how dissolved chemical molecules can stabilize the polar phase in active suspensions.
• To analyze the phase diagrams and stability of active systems with chemically mediated interactions.

Main Methods:

• Linear stability analysis was performed on active systems with different dynamics (momentum conserving and non-conserving).
• Phase diagrams were investigated for systems with chemically mediated long-range interactions.

Main Results:

• Dissolved chemical molecules act as mediators for long-range interactions, stabilizing the polar phase.
• The stabilization mechanism is effective for various swimmer types (pushers, pullers) and geometries (spherical, oblate, prolate).

Conclusions:

• Chemical communication between swimmers is a key mechanism for stabilizing active polar phases.
• This finding offers a new perspective on controlling the behavior of active matter systems.