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Abstract This paper describes how moiré plasmonic nanoparticle lattices can exhibit lasing action over a broad wavelength and wavevector range. Moiré nanolithography is combined with the PEEL (Photolithography, Etching, Electron‐beam deposition, and Lift‐off) process to fabricate in‐plane incommensurate lattices with optical properties beyond the restricted geometries of Bravais lattices. Because of increased rotational symmetry, moiré lattices support a larger number of transverse electric and transverse magnetic modes relative to their periodic base lattices. It is found that multidirectional lasing characteristics can be predicted by the symmetry of the moiré reciprocal lattice. Incommensurate moiré plasmonic lattices combine advantages of the dense band structures observed in aperiodic lattices with that of predicted modes in Bravais lattices for light‐based technologies in coherent light sources and multiplexed data transfer.
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A constructive framework for discovery, design, and classification of volumetric Bravais weaves
Abstract Woven fabrics have a long history of study across the fields of art, mathematics, and mechanics. While weaves with symmetries in R2 have been extensively formalized, classified, and characterized, a systematic framework for representing and designing weaves in R3 remains absent. Despite their relevance to engineering applications—particularly in composite materials—volumetric weaves are often designed in an ad hoc manner, typically by stacking planar weaves and introducing trivial thread connections along the stacking axis. In this article, we establish a formal framework for volumetric weaves by defining them through the isometries of Bravais lattices and their corresponding Voronoi cells in R3. This approach provides a structured description of the design space for a specific family of volumetric weaves, which we call volumetric Bravais weaves. As an example of volumetric Bravais weaves, we analyze, cubic primitive weaves (cP-weaves) in detail as the simplest example within the volumetric Bravais weave framework. This example demonstrates how volumetric Bravais weave structures naturally emerge from 3D lattice isometries. Furthermore, we show that all possible cP-weaves can be systematically generated using a set of cP lattice isometries and cube isometries. Our findings reveal that even just the space of cP-weaves is at least one order of magnitude larger than that of conventional two-way 2-fold weaves, highlighting the potential of our approach for expanding the design space of volumetric weaves.
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- Award ID(s):
- 2048182
- PAR ID:
- 10692445
- Editor(s):
- Harris, Michael
- Publisher / Repository:
- National Academy of Sciences (NAS) in partnership with Oxford University Press (OUP)
- Date Published:
- Journal Name:
- PNAS Nexus
- Volume:
- 4
- Issue:
- 8
- ISSN:
- 2752-6542
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1093/pnasnexus/pgaf219
