Abstract
The ability to dictate the motion of microscopic objects is an important challenge in fields ranging from materials science to biology. Field-directed assembly drives microparticles along paths defined by energy gradients. Nematic liquid crystals, consisting of rod-like molecules, provide new opportunities in this domain. Deviations of nematic liquid crystal molecules from uniform orientation cost elastic energy, and such deviations can be molded by bounding vessel shape. Here, by placing a wavy wall in a nematic liquid crystal, we impose alternating splay and bend distortions, and define a smoothly varying elastic energy field. A microparticle in this field displays a rich set of behaviors, as this system has multiple stable states, repulsive and attractive loci, and interaction strengths that can be tuned to allow reconfigurable states. Microparticles can transition between defect configurations, move along distinct paths, and select sites for preferred docking. Such tailored landscapes have promise in reconfigurable systems and in microrobotics applications.
Highlights
The ability to dictate the motion of microscopic objects is an important challenge in fields ranging from materials science to biology
We combine the effects of the nematic liquid crystals (NLCs) elastic energy field and of an external field to demonstrate fine-tuning of the particles’ sensitivity to the size of their docking sites
Strategies developed within NLCs are one means to address these needs
Summary
The ability to dictate the motion of microscopic objects is an important challenge in fields ranging from materials science to biology. External applied fields provide important additional degrees of freedom, and allow microparticles to be moved along energy gradients with exquisite control In this context, nematic liquid crystals (NLCs) provide unique opportunities[4]. The elastic energy landscapes obtainable with a wavy wall are far richer, and provide important opportunities to direct colloidal motion that go far beyond near-wall lock-and-key interaction. In this system, elastic energy gradients are defined in a nonsingular director field by the wavelength and amplitude of the wavy structure, allowing long ranged wall-colloid interactions. We combine the effects of the NLC elastic energy field and of an external field (gravity) to demonstrate fine-tuning of the particles’ sensitivity to the size of their docking sites
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
