Double symmetry breaking in filamentous colloidal tactoids

Area of Science:

• Soft Matter Physics
• Materials Science
• Liquid Crystals

Background:

• Liquid crystalline tactoids have potential applications in optics, medical devices, and displays.
• Systematic studies of tactoid dynamics under external forces, especially shear flow, are emerging.

Purpose of the Study:

• To investigate the deformation dynamics of liquid crystalline tactoids under shear flow.
• To understand how varying shear conditions and time scales affect tactoid behavior.
• To explore the role of mesoscopic chirality in tactoid deformation.

Main Methods:

• Formation of tactoids using amyloids and nanocellulose with opposite chirality amplification.
• Subjecting tactoids to controlled shear flow fields.
• Observing and analyzing tactoid shape and internal nematic field orientation.

Main Results:

• Tactoids exhibit complex deformation mechanisms under shear flow.
• A double symmetry breaking occurs in tactoid contour shape (kink emergence) and nematic field orientation.
• Mesoscopic chirality of constituent colloids directs the kink's position, mirroring macroscopic asymmetry.

Conclusions:

• The study reveals a complex deformation pathway for liquid crystalline tactoids under shear.
• Mesoscopic chirality is a key factor controlling tactoid asymmetry and internal structure under flow.
• Findings provide fundamental insights for designing materials with tunable optical and mechanical properties.