Three-dimensional crystals of adaptive knots
Starting with Gauss and Kelvin, knots in fields were postulated to behave like particles, but experimentally they were found only as transient features or required complex boundary conditions to exist and could not self-assemble into three-dimensional crystals. We introduce energetically stable, micrometer-sized knots in helical fields of chiral liquid crystals. While spatially localized and freely diffusing in all directions, they resemble colloidal particles and atoms, self-assembling into crystalline lattices with open and closed structures. These knots are robust and topologically distinct from the host medium, though they can be morphed and reconfigured by weak stimuli under conditions such as those in displays. A combination of energy-minimizing numerical modeling and optical imaging uncovers the internal structure and topology of individual helical field knots and the various hierarchical crystalline organizations that they form.
Authors:
;
Award ID(s):
Publication Date:
NSF-PAR ID:
10140862
Journal Name:
Science
Volume:
365
Issue:
6460
Page Range or eLocation-ID:
1449 to 1453
ISSN:
0036-8075
National Science Foundation
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