Tunable topological valence in nematic shells on spherocylindrical colloidal particles

Area of Science:

• Soft matter physics
• Materials science
• Nanotechnology

Background:

• Nematic shells exhibit complex orientational ordering.
• Topological defects influence material properties.
• Colloidal particles are key components in advanced materials.

Purpose of the Study:

• To investigate the orientational ordering and topological defects in nematic shells formed by spherocylindrical colloidal particles.
• To understand the effect of external electric fields on defect structures.
• To explore the potential of these systems as building blocks for nanophotonic devices.

Main Methods:

• Molecular dynamics simulations were employed.
• The study focused on degenerate planar anchoring conditions.
• External electric fields were applied along different axes.

Main Results:

• In the absence of an electric field, spherical cups showed pairs of +1/2 topological defects at the poles and additional ±1/2 defect pairs, totaling eight valence spots.
• A strong axial electric field coalesced polar defects into a single +1 topological defect.
• A strong transverse electric field eliminated defects on spherical cups but created four +1/2 defects in the cylindrical region.

Conclusions:

• External electric fields can precisely control the number and type of valence centers in nematic shells.
• Spherocylindrical nematic shells demonstrate potential as versatile, multivalent building blocks for nanophotonic applications.
• The findings open avenues for designing tunable soft matter systems for advanced optical devices.