Impact of random-field-type disorder on nematic liquid crystalline structures

Area of Science:

• Materials Science
• Soft Matter Physics
• Physical Chemistry

Background:

• Bicomponent systems with liquid crystalline (LC) phases are crucial for understanding order disruption.
• Random perturbations significantly impact orientational and translational order in LC materials.
• Analyzing these perturbations provides insights into fundamental LC behavior.

Purpose of the Study:

• To systematically analyze the impact of different random perturbations on LC order.
• To probe orientational order in nematic LCs and translational order in smectic A LCs.
• To understand the interplay of elastic, interfacial, and random forces in complex LC systems.

Main Methods:

• Review of experimental systems involving LCs perturbed by porous matrices (e.g., control-pore glass, aerogels) and aerosil nanoparticles.
• Characterization of LC ordering using techniques sensitive to orientational and translational order.
• Analysis of fractal-like network organizations formed by perturbing agents within LCs.

Main Results:

• LC ordering in perturbed systems exhibits long-range, quasi long-range, or short-range order.
• Demonstration of conditions under which random-field-like phenomena or interfacial effects dominate.
• Identification of the complex interplay between LC elastic forces, interfacial forces, and randomness.

Conclusions:

• The study highlights the entangled nature of random-field and interfacial effects in experimental LC systems.
• Precise identification of individual impacts of perturbations remains challenging due to their strong entanglement.
• Understanding these interactions is key to designing and controlling LC-based materials.