Tunable large-scale regular array of topological defects in nematic liquid crystals

Area of Science:

• Materials Science
• Condensed Matter Physics
• Optics

Background:

• Liquid crystals exhibit coexisting isotropic and anisotropic phases, forming ordered topological defect arrays.
• These arrays create unique optical pathways for applications in photonics, optics, and self-assembly.
• Current methods lack tunability, hindering practical device implementation.

Purpose of the Study:

• To demonstrate single-domain, tunable arrays of topological defects in nematic liquid crystals.
• To develop a method for fabricating defect arrays with controllable periodicity and domain size.
• To enable the design of scalable, optically functional device architectures.

Main Methods:

• Utilized periodic lateral modulation of electric fields via incompletely etched electrodes with patterned conductivity.
• Employed a method inspired by Orihara and colleagues for defect array generation.
• Investigated the influence of electric field strength, frequency, and electrode geometry on array characteristics.

Main Results:

• Achieved single-domain, tunable arrays of topological defects in nematic liquid crystals.
• Demonstrated control over the period (defect spacing) of the arrays.
• Showcased tunability through electric field parameters and electrode design.

Conclusions:

• The developed method allows for the creation of large-scale, single-domain, tunable defect arrays.
• These findings pave the way for novel, optically functional photonic devices and metamaterials.
• The approach offers a scalable and versatile platform for advanced liquid crystal device engineering.