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Abstract Colloidal crystals are used to understand fundamentals of atomic rearrangements in condensed matter and build complex metamaterials with unique functionalities. Simulations predict a multitude of self-assembled crystal structures from anisotropic colloids, but these shapes have been challenging to fabricate. Here, we use two-photon lithography to fabricate Archimedean truncated tetrahedrons and self-assemble them under quasi-2D confinement. These particles self-assemble into a hexagonal phase under an in-plane gravitational potential. Under additional gravitational potential, the hexagonal phase transitions into a quasi-diamond two-unit basis. In-situ imaging reveal this phase transition is initiated by an out-of-plane rotation of a particle at a crystalline defect and causes a chain reaction of neighboring particle rotations. Our results provide a framework of studying different structures from hard-particle self-assembly and demonstrates the ability to use confinement to induce unusual phases.
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Self-Assembly and Transport Phenomena of Colloids: Confinement and Geometrical Effects
AbstractColloidal dispersions exhibit rich equilibrium and nonequilibrium thermodynamic properties, self-assemble into diverse structures at different length scales, and display transport behavior under bulk conditions. In confinement or under geometrical restrictions, new phenomena emerge that have no counterpart when the colloids are embedded in an open, noncurved space. In this review, we focus on the effects of confinement and geometry on the self-assembly and transport of colloids and fluidized granular systems, which serve as model systems. Our goal is to summarize experiments, theoretical approximations and molecular simulations that provide physical insight on the role played by the geometry at the mesoscopic scale. We highlight particular challenges, and show preliminary results based on the covariant Smoluchowski equation, that present promising avenues to study colloidal dynamics in a non-Euclidean geometry.
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- Award ID(s):
- 1904531
- PAR ID:
- 10571851
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Condensed Matter Physics
- ISSN:
- 1947-5454
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1146/annurev-conmatphys-041124-120513
